World's most beautiful couple: and the figures to prove it
By Roger Dobson
The Independent
Sunday, 11 March 2007
It is the holy grail of the fashion and beauty industries: a scientific blueprint for the most beautiful women, and men, in the world.
Researchers have thrown away the old vital statistics and, instead, focused on how the dimensions of different parts of the body relate to height and body mass index (BMI) to give the perfect physique. Perhaps surprisingly, two of the most important measurements are the girth of the thigh and the slimness of the calf.
The researchers, from the University of Gdansk in Poland, studied the vital statistics of 24 finalists in a national beauty competition, together with those of 115 other women. They said that while weight, height and hip ratio were normally used to assess female attractiveness, these might not throw up crucial differences between the super-attractive and others.
For men, scientists said height, BMI, waist-to-hip and waist-to-chest ratios were key measures.
Super-attractive women had a thigh-to-height ratio some 12 per cent lower than other women, giving them a more slender look. Skinfold tests on the calf showed 15mm of fat compared with 18mm in other women.
The study also showed that the average super-attractive height was 5ft 9in, with the waist 76 per cent of the size of the chest, and 70 per cent of the size of the hips. Models built like Naomi Campbell came closest to the ideal.
"Attractiveness of a woman's body is one of the most important factors in mate selection, and the question what are the physical cues for the assessment of attractiveness is fundamental to evolutionary psychology," said Leszek Pokrywka, who led the study.
Perfect woman: Naomi Campbell
The vital statistics:
Body mass index 20.85
Bust girth to height 49.3%
Waist-chest ratio 1.4
Leg-to-body ratio 1.4
Calf girth to height 19.5%
Height 175cm
Thigh girth to height 29.7
What it all means:
"Super beautiful" women have waists a third smaller than their hips and three-quarters their bust measurement. They have longer legs, and slimmer thighs and calves than the average woman.
Perfect man: Christian Bale
The vital statistics:
Body mass index 26.5
Waist-chest ratio 0.6
Leg-to-body ratio 1
Height 188cm
What it all means:
The physically ideal man is more than 6ft tall, with legs the same length as his upper body. The leg-to-body ratio of 1 makes him appear more muscular, which is why the ideal BMI for men is higher than for women.
beauty
Showing posts with label genes. Show all posts
Showing posts with label genes. Show all posts
Monday, June 14, 2010
Monday, May 10, 2010
Male Extinction
Good-bye males. Brave New World, women only.
The infertility timebomb: Are men facing rapid extinction?
By Tamara Sturtz
Last updated at 8:19 AM on 10th May 2010
Daily Mail.co.uk
One in five men could suffer from fertility problems. And scientists have warned that it's just going to get worse...
There's a crisis brewing, but it has nothing to do with the economic deficit or the current political uncertainty. Scientists are warning that rising levels of male infertility have become so perilous that it is a serious 'public health issue'. And some go even further.
Professor Niels Skakkebaek, of the University of Copenhagen, describes the issue 'as important as global warming'. Last week, one science writer even suggested, in starkly terrifying terms, that if scientists from Mars were to study the male reproductive system, they would possibly conclude that man was destined for rapid extinction.
And if it continues, this trend could indicate men are on a path to becoming completely infertile within a few generations.
Reports claim that as many as one in five healthy young men between the ages of 18 and 25 produce abnormal sperm counts.
Only 5 to 15 per cent of their sperm is good enough to be classed as 'normal' under World Health organisation rules - proving that infertility is not just a female problem. Indeed, among those experiencing difficulty with conception, a male fertility problem is considered important in about 40 per cent of couples.
But women trying to get pregnant are facing another astonishing claim: that the core problems of male fertility - while they may be exacerbated by environmental issues - start in the womb.
'Sperm counts are declining and there is mounting evidence that the problem starts even before birth,' says Dr Gillian Lockwood, medical director of Midland Fertility Services.
She cites growing evidence that although the process of sperm production - known as spermatogenesis - starts in adolescence, the crucial preparations are made in the few months before and after birth.
Factors such as women eating a lot of beef during pregnancy - which means they have consumed a diet rich in polycyclic aromatic hydrocarbons (PAHs) that are potentially damaging chemicals - to the issue of obesity during pregnancy and a woman's exposure to smoke, pesticides, traffic fumes, plastics and even soya beans are all thought to have a bearing on a male foetus's future fertility.
Experts talk of a 'window' of testicular development that begins in the growing foetus and ends in the first six months of life. Problems in this period mean that the baby boy may never be able to produce babies of his own.
It's a theory that Karl Tonks, a clinical skills trainer, is particularly interested in. Karl, 47, and his teaching assistant wife Lorraine, 41, consider themselves among the lucky ones: they have two healthy children, despite Karl's low sperm count. Their twins Ben and Kira, now 12, were born as a result of arduous and expensive IVF.
Like many men, Karl was given no particular reason for his low sperm count. The news that it would be impossible for him to have a child came as a shock.
'We'd been trying for a baby since we got married. I had no idea there was a problem, and there was never a reason given. It was just one of those things.'
Was it, though? Karl admits that he always wondered if the fact that his mother took Thalidomide while pregnant with him could have had any influence on his infertility.
'My mother took Thalidomide for morning sickness. When the scandal broke in 1962, GPs offered free abortions, but my mother was too far gone by two weeks.'
Unlike the majority of Thalidomide babies, Karl was born seemingly healthy. But he has suffered from asthma since birth.
'Since the infertility was diagnosed, I started questioning whether there were underlying problems caused by the drug. My younger brother doesn't have any fertility problems. Nobody has done research into "normal" Thalidomide babies.'
Lorraine and Karl illustrate perfectly the toll that difficulties in conceiving can take on a marriage. Karl confesses that, so distraught were they - 'eight years of thinking of nothing else' is how he puts it - that at one stage he suggested they should divorce. But Lorraine says: 'I just couldn't even think of it.'
After a series of failed intracytoplasmic sperm injection (ICSI) attempts, where Karl's sperm was placed in Lorraine's uterus, the couple moved on to IVF.
The treatment involved intracytoplasmic sperm injection (ICSI), a procedure where a single sperm is injected into the egg. Even though a single healthy sperm could not be found, Karl was able to have testicular sperm extraction (TESE), which involves passing a needle into the testis to remove a piece of tissue, from which developing sperm were taken.
Incredibly, that resulted in eight fertilised embryos. In April 1998 their twins, Ben and Kira, were born. Their father drove down the street shouting: 'I'm a dad!'
Like Lorraine and Karl, Ed Farmer, 41, an IT specialist, and his wife, Rebecca, also 41, are still left guessing as to the causes of Ed's infertility.
'We were told that Ed had practically zero per cent sperm,' says Rebecca.
But after seven years of tests and treatment, they are no closer to knowing why.
'It was a terrible shock and desperately disappointing to be facing the possibility of IVF,' explains Ed.
Their fertility consultant recommended ICSI. Both Ed and Rebecca were 33, and their hopes were high, especially after several healthy sperm were retrieved using TESE.
'We believed our consultant when he said: "Let's make you a baby",' says Ed.
But treatment failed and they were told to consider using donor sperm. However, they went through two more cycles of treatment.
'We wanted to give it everything we could,' explains Ed. By this time, they were both 35.
'We had to make some major decisions', says Rebecca. It was putting a huge strain on their relationship, and they had withdrawn from their friends and family.
'We felt it was us against the world,' says Rebecca. 'We were so fed up of everyone around us having babies and not understanding what we were going through. Comments such as "At least you have a lovely husband and a nice house" weren't helpful. We even considered moving abroad.'
Rebecca threw herself into researching multiple IVF and ICSI failure on the internet, and concluded that not all clinics are the same.
Ed says: 'It was important for me to see an andrologist, somebody who specialises in male infertility. But they are not readily available in the UK.'
'We looked at it very rationally and were prepared to spend £15,000,' says Rebecca.
Research had been carried out in the U.S. in hormonal therapy for men with fertility problems. After remortgaging their home, Ed and Rebecca went to New York.
'I had the first proper examination throughout all our treatment,' says Ed.
He was put on Clomid, the hormone that women are given when they don't ovulate regularly, followed by ICSI. Although this created only one embryo, it resulted in the birth of their beautiful daughter, Ruby, now three.
Ed and Rebecca wanted a sibling for Ruby. After another cycle of treatment in New York, their twins, Tom and Rose, were born two days before Rebecca's 40th birthday.
Ed and Rebecca are very proud parents and thrilled that they defied the odds. But they are also angry.
' So many men are denied the opportunity to become biological fathers through an apparent lack of investigation into male infertility,' says Rebecca.
'We have met couples who have gone through many failed cycles of treatment at great financial and emotional cost, who have gone on to have "miracle babies" abroad, after being dismissed by UK clinics. It is so sad that the country that invented IVF should have failed to progress much beyond the expensive and impersonal production line of treatment that is currently on offer.'
Meanwhile, Lorraine and Karl Tonks are following the latest research with interest. It suggests that if their son Ben is to have fertility problems of his own, it may be too late to do anything about it. This concerns Karl.
'I worry that I may have passed my infertility on to my son. He has asthma, but as there are no adult ICSI children yet, we probably won't know for another few years.
'I will encourage him to get his fertility checked when he is old enough.'
Lorraine, however, points out that there are drawbacks to knowing too much, too soon.
'On the one hand, if we'd known earlier that there was no chance of us getting pregnant naturally, then we'd have saved a lot of time and heartache, seeking help sooner. On the other hand, can I honestly say that we would have ended up married had I known Karl couldn't have children? Who knows? It's very tricky.'
It will get even trickier as more efforts are made to unravel the mystery of male sperm production, a mystery to which 'Mother', whether she likes it or not, seems to hold the key.
genetics
The infertility timebomb: Are men facing rapid extinction?
By Tamara Sturtz
Last updated at 8:19 AM on 10th May 2010
Daily Mail.co.uk
One in five men could suffer from fertility problems. And scientists have warned that it's just going to get worse...
There's a crisis brewing, but it has nothing to do with the economic deficit or the current political uncertainty. Scientists are warning that rising levels of male infertility have become so perilous that it is a serious 'public health issue'. And some go even further.
Professor Niels Skakkebaek, of the University of Copenhagen, describes the issue 'as important as global warming'. Last week, one science writer even suggested, in starkly terrifying terms, that if scientists from Mars were to study the male reproductive system, they would possibly conclude that man was destined for rapid extinction.
And if it continues, this trend could indicate men are on a path to becoming completely infertile within a few generations.
Reports claim that as many as one in five healthy young men between the ages of 18 and 25 produce abnormal sperm counts.
Only 5 to 15 per cent of their sperm is good enough to be classed as 'normal' under World Health organisation rules - proving that infertility is not just a female problem. Indeed, among those experiencing difficulty with conception, a male fertility problem is considered important in about 40 per cent of couples.
But women trying to get pregnant are facing another astonishing claim: that the core problems of male fertility - while they may be exacerbated by environmental issues - start in the womb.
'Sperm counts are declining and there is mounting evidence that the problem starts even before birth,' says Dr Gillian Lockwood, medical director of Midland Fertility Services.
She cites growing evidence that although the process of sperm production - known as spermatogenesis - starts in adolescence, the crucial preparations are made in the few months before and after birth.
Factors such as women eating a lot of beef during pregnancy - which means they have consumed a diet rich in polycyclic aromatic hydrocarbons (PAHs) that are potentially damaging chemicals - to the issue of obesity during pregnancy and a woman's exposure to smoke, pesticides, traffic fumes, plastics and even soya beans are all thought to have a bearing on a male foetus's future fertility.
Experts talk of a 'window' of testicular development that begins in the growing foetus and ends in the first six months of life. Problems in this period mean that the baby boy may never be able to produce babies of his own.
It's a theory that Karl Tonks, a clinical skills trainer, is particularly interested in. Karl, 47, and his teaching assistant wife Lorraine, 41, consider themselves among the lucky ones: they have two healthy children, despite Karl's low sperm count. Their twins Ben and Kira, now 12, were born as a result of arduous and expensive IVF.
Like many men, Karl was given no particular reason for his low sperm count. The news that it would be impossible for him to have a child came as a shock.
'We'd been trying for a baby since we got married. I had no idea there was a problem, and there was never a reason given. It was just one of those things.'
Was it, though? Karl admits that he always wondered if the fact that his mother took Thalidomide while pregnant with him could have had any influence on his infertility.
'My mother took Thalidomide for morning sickness. When the scandal broke in 1962, GPs offered free abortions, but my mother was too far gone by two weeks.'
Unlike the majority of Thalidomide babies, Karl was born seemingly healthy. But he has suffered from asthma since birth.
'Since the infertility was diagnosed, I started questioning whether there were underlying problems caused by the drug. My younger brother doesn't have any fertility problems. Nobody has done research into "normal" Thalidomide babies.'
Lorraine and Karl illustrate perfectly the toll that difficulties in conceiving can take on a marriage. Karl confesses that, so distraught were they - 'eight years of thinking of nothing else' is how he puts it - that at one stage he suggested they should divorce. But Lorraine says: 'I just couldn't even think of it.'
After a series of failed intracytoplasmic sperm injection (ICSI) attempts, where Karl's sperm was placed in Lorraine's uterus, the couple moved on to IVF.
The treatment involved intracytoplasmic sperm injection (ICSI), a procedure where a single sperm is injected into the egg. Even though a single healthy sperm could not be found, Karl was able to have testicular sperm extraction (TESE), which involves passing a needle into the testis to remove a piece of tissue, from which developing sperm were taken.
Incredibly, that resulted in eight fertilised embryos. In April 1998 their twins, Ben and Kira, were born. Their father drove down the street shouting: 'I'm a dad!'
Like Lorraine and Karl, Ed Farmer, 41, an IT specialist, and his wife, Rebecca, also 41, are still left guessing as to the causes of Ed's infertility.
'We were told that Ed had practically zero per cent sperm,' says Rebecca.
But after seven years of tests and treatment, they are no closer to knowing why.
'It was a terrible shock and desperately disappointing to be facing the possibility of IVF,' explains Ed.
Their fertility consultant recommended ICSI. Both Ed and Rebecca were 33, and their hopes were high, especially after several healthy sperm were retrieved using TESE.
'We believed our consultant when he said: "Let's make you a baby",' says Ed.
But treatment failed and they were told to consider using donor sperm. However, they went through two more cycles of treatment.
'We wanted to give it everything we could,' explains Ed. By this time, they were both 35.
'We had to make some major decisions', says Rebecca. It was putting a huge strain on their relationship, and they had withdrawn from their friends and family.
'We felt it was us against the world,' says Rebecca. 'We were so fed up of everyone around us having babies and not understanding what we were going through. Comments such as "At least you have a lovely husband and a nice house" weren't helpful. We even considered moving abroad.'
Rebecca threw herself into researching multiple IVF and ICSI failure on the internet, and concluded that not all clinics are the same.
Ed says: 'It was important for me to see an andrologist, somebody who specialises in male infertility. But they are not readily available in the UK.'
'We looked at it very rationally and were prepared to spend £15,000,' says Rebecca.
Research had been carried out in the U.S. in hormonal therapy for men with fertility problems. After remortgaging their home, Ed and Rebecca went to New York.
'I had the first proper examination throughout all our treatment,' says Ed.
He was put on Clomid, the hormone that women are given when they don't ovulate regularly, followed by ICSI. Although this created only one embryo, it resulted in the birth of their beautiful daughter, Ruby, now three.
Ed and Rebecca wanted a sibling for Ruby. After another cycle of treatment in New York, their twins, Tom and Rose, were born two days before Rebecca's 40th birthday.
Ed and Rebecca are very proud parents and thrilled that they defied the odds. But they are also angry.
' So many men are denied the opportunity to become biological fathers through an apparent lack of investigation into male infertility,' says Rebecca.
'We have met couples who have gone through many failed cycles of treatment at great financial and emotional cost, who have gone on to have "miracle babies" abroad, after being dismissed by UK clinics. It is so sad that the country that invented IVF should have failed to progress much beyond the expensive and impersonal production line of treatment that is currently on offer.'
Meanwhile, Lorraine and Karl Tonks are following the latest research with interest. It suggests that if their son Ben is to have fertility problems of his own, it may be too late to do anything about it. This concerns Karl.
'I worry that I may have passed my infertility on to my son. He has asthma, but as there are no adult ICSI children yet, we probably won't know for another few years.
'I will encourage him to get his fertility checked when he is old enough.'
Lorraine, however, points out that there are drawbacks to knowing too much, too soon.
'On the one hand, if we'd known earlier that there was no chance of us getting pregnant naturally, then we'd have saved a lot of time and heartache, seeking help sooner. On the other hand, can I honestly say that we would have ended up married had I known Karl couldn't have children? Who knows? It's very tricky.'
It will get even trickier as more efforts are made to unravel the mystery of male sperm production, a mystery to which 'Mother', whether she likes it or not, seems to hold the key.
genetics
Monday, April 26, 2010
Goodbye MANkind, you proved useful once, but now, an inconvenience at best. All the wars, anguish, suffering you put the world through - all the machismo, hitting, whacking, kicking, fighting, and otherwise unnecessary physical activity ... your time has come. The rest of Earth will be just fine without you. Science has seen to that.
Out for the count: Why levels of sperm in men are falling
Levels of 'viable' sperm in human males are falling – and scientists believe they now understand the cause. Infertility can begin in the womb, says Steve Connor
Monday, 26 April 2010
The Independent
If scientists from Mars were to study the human male's reproductive system they would probably conclude that he is destined for rapid extinction. Compared to other mammals, humans produce relatively low numbers of viable sperm – sperm capable of making that long competitive swim to penetrate an unfertilised egg.
As many as one in five healthy young men between the ages of 18 and 25 produce abnormal sperm counts. Even the sperm they do produce is often of poor quality. In fact only between 5 and 15 per cent of their sperm is, on average, good enough to be classed as "normal" under strict World Health Organisation rules – and these are young, healthy men. By contrast, more than 90 per cent of the sperm of a domestic bull or ram, or even laboratory rat, are normal.
Human males also suffer a disproportionately high incidence of reproductive problems, from congenital defects and undescended testes to cancer and impotency. As these also affect fertility, it's a minor miracle men are able to sire any children at all. In fact, an increasing number of men are finding themselves childless. Among the one in seven couples now classed as infertile, the "male factor" has been found to be the most commonly identified cause.
Next year marks the 20th anniversary of the WHO conference where a Danish scientist first alerted the world to the fact that Western men are suffering an infertility crisis. Professor Niels Skakkebaek of the University of Copenhagen presented data indicating sperm counts had fallen by about a half over the past 50 years. Sperm counts in the 1940s were typically well above 100m sperm cells per millilitre, but Professor Skakkebaek found they have dropped to an average of about 60m per ml. Other studies found that between 15 and 20 per cent of young men now find themselves with sperm counts of less than 20m per ml, which is technically defined as abnormal. In contrast, a dairy bull has a viable sperm count in the billions.
Experts in human reproductive biology were astonished by the Danish study. The declining trend seemed to indicate that men were on a path to becoming completely infertile within a few generations (although recent studies suggest the fall in sperm counts may have bottomed out). Professor Skakkebaek could offer no explanation for the trend other than to suggest that the fall may have something to do with the equally alarming rise in other reproductive disorders, such as cancer of the testes and cryptorchidism, the incomplete descent of the testes into the scrotum.
Experts began to talk of a new phenomenon affecting the human male, a collection of disorders known as testicular dysgenesis syndrome. They wanted to know what was causing it, because the changes were occurring too quickly to be a result of genetics. It must have something to with changing lifestyles or the environment of men, and almost everything was suggested, from exposure to chemical pollutants to the modern fashion for tight underpants. There is now an emerging consensus among some experts that whatever it is that is exacerbating the problems of male infertility, it probably starts in the womb. It is not the lifestyle of men that is problem, but that of their mothers.
The process of sperm production, called spermatogenesis, starts in adolescence, but the groundwork is laid down in the few months before and immediately after birth. An increasing number of studies point to a crucial "window" of testicular development that begins in the growing foetus and ends in the first six months of life. Interfere with this critical developmental period, and a baby boy will suffer the lifetime consequences of being a suboptimally fertile man.
So are we anywhere nearer to finding an explanation for why are so many more men today are suffering from reproductive problems?
"It's most likely a reflection of the fact that many environmental and lifestyle changes over the past 50 years are inherently detrimental to sperm production," says Professor Richard Sharpe, fertility research expert at the Medical Research Council. "It may be that different factors come together to have a combined effect." A number of studies point to a connection between early development in the womb and male reproductive problems in later life, especially low sperm counts. For example, men whose pregnant mothers were exposed to high levels of toxic dioxins as a result of the 1976 industrial accident in Seveso, Italy have been found to have lower-than-average sperm counts. But men exposed to dioxins in adulthood showed no such effect. Another study found women who ate large amounts of beef during pregnancy, a diet rich in potentially damaging chemicals called polycyclic aromatic hydrocarbons (PAHs), had sons with relatively low sperm counts. But eating beef as an adult man shows no similar impact.
Meanwhile, studies of migrants between Sweden and Finland, showed that a man's lifetime risk of testicular cancer tends to follow the country he was born in rather than the country where he was brought up. It was his mother's environment when she was pregnant with him, rather than his own as a boy or as an adolescent, that seems to have largely determined a man's risk of testicular cancer.
One of the strongest pieces of evidence in support of this idea comes from studies of people who smoke. A man who smokes typically reduces his sperm count by a modest 15 per cent or so, which is probably reversible if he quits. However, a man whose mother smoked during pregnancy has a fairly dramatic decrease in sperm counts of up to 40 per cent – which also tends to be irreversible.
Professor Sharpe said such findings can be explained by understanding how the first cells of the testes form. Sertoli cells, which in the adult act as guardians for the development of sperm cells, are the very first cells to form from a "genital ridge" of the human male foetus. The number of sperm that can be produced in an adult man is critically dependent on the number of Sertoli cells that develop in his foetus, so anything that interferes with the formation of Sertoli cells in a mother's womb will affect sperm production many years later. "Maternal-lifestyle factors in pregnancy can have quite substantial effects on sperm counts in sons in adulthood, and the most logical mechanism by which this could occur is via reducing the number of Sertoli cells," Professor Sharpe says.
But the key question now is to identify the relevant lifestyle and environmental factors.
This is proving tricky. Obesity, for instance, is a growing problem and it has been linked with reproductive problems in both men and women. One study has also indicated that overweight pregnant women tend to produce sons with poor semen quality. But is it being fat that is the cause, or the environmental chemicals stored in fat?
There has been a lot of interest in chemicals in the environment, especially those that can either mimic female sex hormones – oestrogenic chemicals – or block male sex hormones, specifically testosterone which plays a critical role in stimulating the development of Sertoli cells in the womb. So far, the Seveso study provides the clearest link between human foetal development, low sperm counts and prenatal exposure to an environmental chemical. But the dioxin concentrations from this industrial accident were exceptionally high.
It is more difficult trying to establish a similar, significant link between male reproductive problems and exposure to low concentrations of the many other environmental chemicals that may have weak oestrogenic or androgen-blocking properties, including substances as wide-ranging as pesticides, traffic fumes, plastics and even soya beans. Professor Sharpe says that much of the evidence to date is weak or non-existent.
"Public concern about the adverse effects of environmental chemicals on spermatogenesis in adult men are, in general, not supported by the available data for humans. Where adverse effects of environmental chemicals have been shown, they are usually in an occupational setting rather than applying to the general population," he says.
So although scientists are closing in on the critical window of foetal development in the womb that determines a man's fertility status in later life, they are still not sure about what it is that could be affecting this change in his reproductive status. But one thing is clear, it is his mother who almost certainly holds the key.
humankind
Out for the count: Why levels of sperm in men are falling
Levels of 'viable' sperm in human males are falling – and scientists believe they now understand the cause. Infertility can begin in the womb, says Steve Connor
Monday, 26 April 2010
The Independent
If scientists from Mars were to study the human male's reproductive system they would probably conclude that he is destined for rapid extinction. Compared to other mammals, humans produce relatively low numbers of viable sperm – sperm capable of making that long competitive swim to penetrate an unfertilised egg.
As many as one in five healthy young men between the ages of 18 and 25 produce abnormal sperm counts. Even the sperm they do produce is often of poor quality. In fact only between 5 and 15 per cent of their sperm is, on average, good enough to be classed as "normal" under strict World Health Organisation rules – and these are young, healthy men. By contrast, more than 90 per cent of the sperm of a domestic bull or ram, or even laboratory rat, are normal.
Human males also suffer a disproportionately high incidence of reproductive problems, from congenital defects and undescended testes to cancer and impotency. As these also affect fertility, it's a minor miracle men are able to sire any children at all. In fact, an increasing number of men are finding themselves childless. Among the one in seven couples now classed as infertile, the "male factor" has been found to be the most commonly identified cause.
Next year marks the 20th anniversary of the WHO conference where a Danish scientist first alerted the world to the fact that Western men are suffering an infertility crisis. Professor Niels Skakkebaek of the University of Copenhagen presented data indicating sperm counts had fallen by about a half over the past 50 years. Sperm counts in the 1940s were typically well above 100m sperm cells per millilitre, but Professor Skakkebaek found they have dropped to an average of about 60m per ml. Other studies found that between 15 and 20 per cent of young men now find themselves with sperm counts of less than 20m per ml, which is technically defined as abnormal. In contrast, a dairy bull has a viable sperm count in the billions.
Experts in human reproductive biology were astonished by the Danish study. The declining trend seemed to indicate that men were on a path to becoming completely infertile within a few generations (although recent studies suggest the fall in sperm counts may have bottomed out). Professor Skakkebaek could offer no explanation for the trend other than to suggest that the fall may have something to do with the equally alarming rise in other reproductive disorders, such as cancer of the testes and cryptorchidism, the incomplete descent of the testes into the scrotum.
Experts began to talk of a new phenomenon affecting the human male, a collection of disorders known as testicular dysgenesis syndrome. They wanted to know what was causing it, because the changes were occurring too quickly to be a result of genetics. It must have something to with changing lifestyles or the environment of men, and almost everything was suggested, from exposure to chemical pollutants to the modern fashion for tight underpants. There is now an emerging consensus among some experts that whatever it is that is exacerbating the problems of male infertility, it probably starts in the womb. It is not the lifestyle of men that is problem, but that of their mothers.
The process of sperm production, called spermatogenesis, starts in adolescence, but the groundwork is laid down in the few months before and immediately after birth. An increasing number of studies point to a crucial "window" of testicular development that begins in the growing foetus and ends in the first six months of life. Interfere with this critical developmental period, and a baby boy will suffer the lifetime consequences of being a suboptimally fertile man.
So are we anywhere nearer to finding an explanation for why are so many more men today are suffering from reproductive problems?
"It's most likely a reflection of the fact that many environmental and lifestyle changes over the past 50 years are inherently detrimental to sperm production," says Professor Richard Sharpe, fertility research expert at the Medical Research Council. "It may be that different factors come together to have a combined effect." A number of studies point to a connection between early development in the womb and male reproductive problems in later life, especially low sperm counts. For example, men whose pregnant mothers were exposed to high levels of toxic dioxins as a result of the 1976 industrial accident in Seveso, Italy have been found to have lower-than-average sperm counts. But men exposed to dioxins in adulthood showed no such effect. Another study found women who ate large amounts of beef during pregnancy, a diet rich in potentially damaging chemicals called polycyclic aromatic hydrocarbons (PAHs), had sons with relatively low sperm counts. But eating beef as an adult man shows no similar impact.
Meanwhile, studies of migrants between Sweden and Finland, showed that a man's lifetime risk of testicular cancer tends to follow the country he was born in rather than the country where he was brought up. It was his mother's environment when she was pregnant with him, rather than his own as a boy or as an adolescent, that seems to have largely determined a man's risk of testicular cancer.
One of the strongest pieces of evidence in support of this idea comes from studies of people who smoke. A man who smokes typically reduces his sperm count by a modest 15 per cent or so, which is probably reversible if he quits. However, a man whose mother smoked during pregnancy has a fairly dramatic decrease in sperm counts of up to 40 per cent – which also tends to be irreversible.
Professor Sharpe said such findings can be explained by understanding how the first cells of the testes form. Sertoli cells, which in the adult act as guardians for the development of sperm cells, are the very first cells to form from a "genital ridge" of the human male foetus. The number of sperm that can be produced in an adult man is critically dependent on the number of Sertoli cells that develop in his foetus, so anything that interferes with the formation of Sertoli cells in a mother's womb will affect sperm production many years later. "Maternal-lifestyle factors in pregnancy can have quite substantial effects on sperm counts in sons in adulthood, and the most logical mechanism by which this could occur is via reducing the number of Sertoli cells," Professor Sharpe says.
But the key question now is to identify the relevant lifestyle and environmental factors.
This is proving tricky. Obesity, for instance, is a growing problem and it has been linked with reproductive problems in both men and women. One study has also indicated that overweight pregnant women tend to produce sons with poor semen quality. But is it being fat that is the cause, or the environmental chemicals stored in fat?
There has been a lot of interest in chemicals in the environment, especially those that can either mimic female sex hormones – oestrogenic chemicals – or block male sex hormones, specifically testosterone which plays a critical role in stimulating the development of Sertoli cells in the womb. So far, the Seveso study provides the clearest link between human foetal development, low sperm counts and prenatal exposure to an environmental chemical. But the dioxin concentrations from this industrial accident were exceptionally high.
It is more difficult trying to establish a similar, significant link between male reproductive problems and exposure to low concentrations of the many other environmental chemicals that may have weak oestrogenic or androgen-blocking properties, including substances as wide-ranging as pesticides, traffic fumes, plastics and even soya beans. Professor Sharpe says that much of the evidence to date is weak or non-existent.
"Public concern about the adverse effects of environmental chemicals on spermatogenesis in adult men are, in general, not supported by the available data for humans. Where adverse effects of environmental chemicals have been shown, they are usually in an occupational setting rather than applying to the general population," he says.
So although scientists are closing in on the critical window of foetal development in the womb that determines a man's fertility status in later life, they are still not sure about what it is that could be affecting this change in his reproductive status. But one thing is clear, it is his mother who almost certainly holds the key.
humankind
Monday, April 19, 2010
Science and Fat People
Well, we will need to remove these genes from babies, or risk serious health care problems later in life. Isn't science wonderful.
Gene makes people fat, raises Alzheimer's risk
By Julie Steenhuysen
April 19, 2010
Reuters
CHICAGO (Reuters) – A variant of an obesity gene carried by more than a third of the U.S. population also reduces brain volume, raising carriers' risk of Alzheimer's disease, U.S. researchers said on Monday.
People with a specific variant of the fat mass and obesity gene, or FTO gene, have brain deficits that could make them more vulnerable to the mind-robbing disease.
"The basic result is that this very prevalent gene not only adds an inch to your waistline, but makes your brain look 16 years older," said Paul Thompson, a professor of neurology at the University of California Los Angeles, who worked on the study published in Proceedings of the National Academy of Sciences.
Brains generally shrink with age.
The study compared brain scans of more than 200 people and found consistently less tissue in the brains of people who carry the "bad" version of the FTO gene compared to non-carriers.
On average, people with the obesity variant of the FTO gene had 8 percent less tissue in their frontal lobes -- sometimes referred to as the brain's "command center." They also had 12 percent less tissue in their occipital lobes, which is the part of the brain that processes vision and other perceptions.
Thompson said reduced brain volume raises a person's risk for Alzheimer's disease by reducing the amount of brain reserve a person has to compensate if the brain plaques linked to Alzheimer's form. Stroke can also reduce brain tissue, depleting the brain's reserve.
DIET AND EXERCISE
The added brain risk means it is more important for people who carry the FTO gene to eat a low-fat diet and exercise regularly, he said.
A 2008 study of Amish people who had the FTO risk gene but were physically active found they weighed about the same as non-carriers, suggesting that physical activity can overcome a genetic predisposition to obesity.
People with two copies of the FTO gene variant on average weigh nearly 7 pounds (3 kg) more and are about 70 percent more likely to be obese than those who do not have the gene.
"In all the maelstrom of activities you do, exercise and a low-fat diet are genuinely saving your brain from both stroke and Alzheimer's," Thompson said.
For the study, Thompson's team compared magnetic resonance images taken of the brains of 206 healthy people between age 55 and 90 at 58 centers. The centers were taking part in the five-year Alzheimer's Disease Neuroimaging Initiative, which is examining the factors that help aging brains resist disease.
Because so many people carry the obesity version of the FTO gene, Thompson said the findings may drive research into new drug compounds to alter the effects on the brain.
Short of that, he said the findings should lead carriers to eat less and exercise more.
There is no cure for Alzheimer's disease, the most common form of dementia affecting 26 million people globally.
Current treatments help with some symptoms, but cannot reverse the course of the disease, leading many scientific teams to look for ways to prevent it.
The study is available at
http://www.pnas.org/cgi/doi/10.1073/pnas.0910878107
fat
Gene makes people fat, raises Alzheimer's risk
By Julie Steenhuysen
April 19, 2010
Reuters
CHICAGO (Reuters) – A variant of an obesity gene carried by more than a third of the U.S. population also reduces brain volume, raising carriers' risk of Alzheimer's disease, U.S. researchers said on Monday.
People with a specific variant of the fat mass and obesity gene, or FTO gene, have brain deficits that could make them more vulnerable to the mind-robbing disease.
"The basic result is that this very prevalent gene not only adds an inch to your waistline, but makes your brain look 16 years older," said Paul Thompson, a professor of neurology at the University of California Los Angeles, who worked on the study published in Proceedings of the National Academy of Sciences.
Brains generally shrink with age.
The study compared brain scans of more than 200 people and found consistently less tissue in the brains of people who carry the "bad" version of the FTO gene compared to non-carriers.
On average, people with the obesity variant of the FTO gene had 8 percent less tissue in their frontal lobes -- sometimes referred to as the brain's "command center." They also had 12 percent less tissue in their occipital lobes, which is the part of the brain that processes vision and other perceptions.
Thompson said reduced brain volume raises a person's risk for Alzheimer's disease by reducing the amount of brain reserve a person has to compensate if the brain plaques linked to Alzheimer's form. Stroke can also reduce brain tissue, depleting the brain's reserve.
DIET AND EXERCISE
The added brain risk means it is more important for people who carry the FTO gene to eat a low-fat diet and exercise regularly, he said.
A 2008 study of Amish people who had the FTO risk gene but were physically active found they weighed about the same as non-carriers, suggesting that physical activity can overcome a genetic predisposition to obesity.
People with two copies of the FTO gene variant on average weigh nearly 7 pounds (3 kg) more and are about 70 percent more likely to be obese than those who do not have the gene.
"In all the maelstrom of activities you do, exercise and a low-fat diet are genuinely saving your brain from both stroke and Alzheimer's," Thompson said.
For the study, Thompson's team compared magnetic resonance images taken of the brains of 206 healthy people between age 55 and 90 at 58 centers. The centers were taking part in the five-year Alzheimer's Disease Neuroimaging Initiative, which is examining the factors that help aging brains resist disease.
Because so many people carry the obesity version of the FTO gene, Thompson said the findings may drive research into new drug compounds to alter the effects on the brain.
Short of that, he said the findings should lead carriers to eat less and exercise more.
There is no cure for Alzheimer's disease, the most common form of dementia affecting 26 million people globally.
Current treatments help with some symptoms, but cannot reverse the course of the disease, leading many scientific teams to look for ways to prevent it.
The study is available at
http://www.pnas.org/cgi/doi/10.1073/pnas.0910878107
fat
Friday, October 23, 2009
Gay Sheep
What to do with gay sheep? Hmm. I know, let's adjust their hormones and see what we can come up with. Hold on, say some folks who fear having homosexuality bred out!
TimesOnline - London Times, December 31, 2006
The Sunday Times
Science told: hands off gay sheep
Isabel Oakeshott and Chris Gourlay
Experiments that claim to "cure" homosexual rams spark anger
Scientists are conducting experiments to change the sexuality of 'gay" sheep ina programme that critics fear could pave the way for breeding out homsexuality in humans.
The technique being developed by American researchers adjusts the hormonal balance in the brains of homosexual rams so that they are more inclined to mate with ewes.
It raises the prospect that pregnant women could one day be offered a treatment to reduce or eliminate the chance their offspring will be homsexual. Experts say that, in theory, the "straightening" procedure on humans could be as simple as a hormone supplement for mother-to-be, worn on the skin like an anti-smoking nicotine patch.
[There is considerably more, but I cannot type it all and the article is not available unless I pay for it.]
One further point from the article -
[Martina] Navratilova defended the "right" of the sheep to be gay. She said: "How can it be that in the year 2006 a major university would host such homophobic and cruel experiments?" She said gay men and lesbians would be "deeply offended" by the social implications of the tests.
gay
TimesOnline - London Times, December 31, 2006
The Sunday Times
Science told: hands off gay sheep
Isabel Oakeshott and Chris Gourlay
Experiments that claim to "cure" homosexual rams spark anger
Scientists are conducting experiments to change the sexuality of 'gay" sheep ina programme that critics fear could pave the way for breeding out homsexuality in humans.
The technique being developed by American researchers adjusts the hormonal balance in the brains of homosexual rams so that they are more inclined to mate with ewes.
It raises the prospect that pregnant women could one day be offered a treatment to reduce or eliminate the chance their offspring will be homsexual. Experts say that, in theory, the "straightening" procedure on humans could be as simple as a hormone supplement for mother-to-be, worn on the skin like an anti-smoking nicotine patch.
[There is considerably more, but I cannot type it all and the article is not available unless I pay for it.]
One further point from the article -
[Martina] Navratilova defended the "right" of the sheep to be gay. She said: "How can it be that in the year 2006 a major university would host such homophobic and cruel experiments?" She said gay men and lesbians would be "deeply offended" by the social implications of the tests.
gay
Monday, March 2, 2009
Genetics: I'll take a blonde female and a boy with brown hair. Wrap em up.
The day has arrived. Actually, it arrived some time ago, but was not as public as it is today.
Goodbye father, goodbye mother ... goodbye family ... hello spawn of science.
Designer baby row over US clinic
BBC News
March 2, 2009
A US clinic has sparked controversy by offering would-be parents the chance to select traits like the eye and hair colour of their offspring.
The LA Fertility Institutes run by Dr Jeff Steinberg, a pioneer of IVF in the 1970s, expects a trait-selected baby to be born next year.
His clinic also offers sex selection.
UK fertility experts are angered that the service will distract attention from how the same technology can protect against inherited disease.
The science is based on a lab technique called preimplantation genetic diagnosis, or PGD.
“ I would not say this is a dangerous road. It's an uncharted road ” Dr Steinberg.
This involves testing a cell taken from a very early embryo before it is put into the mother's womb.
Doctors then select an embryo free from rogue genes - or in this case an embryo with the desired physical traits such as blonde hair and blue eyes - to continue the pregnancy, and discard any others.
Dr Steinberg said couples might seek to use the clinic's services for both medical and cosmetic reasons.
For example, a couple might want to have a baby with a darker complexion to help guard against a skin cancer if they already had a child who had developed a melanoma. But others might just want a boy with blonde hair.
His clinic is offering this cosmetic selection to patients already having genetic screening for abnormal chromosome conditions in their embryos.
“ This is the inevitable slippery slope of a fertility process which results in many more embryos being created than can be implanted ” Josephine Quintavalle of Comment on Reproductive Ethics.
"Not all patients will qualify for these tests and we make NO guarantees as to 'perfect prediction' of things such as eye colour or hair colour," says the clinic's website.
Dr Steinberg said: "I would not say this is a dangerous road. It's an uncharted road."
He said the capability to offer such services had been around for years, but had been ignored by the medical community.
"It's time for everyone to pull their heads out of the sand."
Slippery slope
But Dr Gillian Lockwood, a UK fertility expert and member of the Royal College of Obstetricians and Gynaecologists' ethics committee, questioned whether is was morally right to be using the science in this way.
"If it gets to the point where we can decide which gene or combination of genes are responsible for blue eyes or blonde hair, what are you going to do with all those other embryos that turn out like me to be ginger with green eyes?"
She warned against "turning babies into commodities that you buy off the shelf."
Josephine Quintavalle of Comment on Reproductive Ethics said: "This is the inevitable slippery slope of a fertility process which results in many more embryos being created than can be implanted. Choices will always have to be made. Do you choose octuplets or the ones with the prettiest noses?"
In the UK, sex selection is banned and choices are currently permitted only in relationship to the baby's health.
Italian fertility law does not permit the creation of surplus embryos or selective testing. Ms Quintavalle said that was "one sure way to avoid the slippery slope".
Meanwhile, new legislation in the UK, due to come in on 6 April, will allow IVF mothers to name anyone as "father" on the birth certificate - even another woman.
The only restriction on naming a second parent will be if they are close blood relatives or if the second person does not agree.
genetics
Goodbye father, goodbye mother ... goodbye family ... hello spawn of science.
Designer baby row over US clinic
BBC News
March 2, 2009
A US clinic has sparked controversy by offering would-be parents the chance to select traits like the eye and hair colour of their offspring.
The LA Fertility Institutes run by Dr Jeff Steinberg, a pioneer of IVF in the 1970s, expects a trait-selected baby to be born next year.
His clinic also offers sex selection.
UK fertility experts are angered that the service will distract attention from how the same technology can protect against inherited disease.
The science is based on a lab technique called preimplantation genetic diagnosis, or PGD.
“ I would not say this is a dangerous road. It's an uncharted road ” Dr Steinberg.
This involves testing a cell taken from a very early embryo before it is put into the mother's womb.
Doctors then select an embryo free from rogue genes - or in this case an embryo with the desired physical traits such as blonde hair and blue eyes - to continue the pregnancy, and discard any others.
Dr Steinberg said couples might seek to use the clinic's services for both medical and cosmetic reasons.
For example, a couple might want to have a baby with a darker complexion to help guard against a skin cancer if they already had a child who had developed a melanoma. But others might just want a boy with blonde hair.
His clinic is offering this cosmetic selection to patients already having genetic screening for abnormal chromosome conditions in their embryos.
“ This is the inevitable slippery slope of a fertility process which results in many more embryos being created than can be implanted ” Josephine Quintavalle of Comment on Reproductive Ethics.
"Not all patients will qualify for these tests and we make NO guarantees as to 'perfect prediction' of things such as eye colour or hair colour," says the clinic's website.
Dr Steinberg said: "I would not say this is a dangerous road. It's an uncharted road."
He said the capability to offer such services had been around for years, but had been ignored by the medical community.
"It's time for everyone to pull their heads out of the sand."
Slippery slope
But Dr Gillian Lockwood, a UK fertility expert and member of the Royal College of Obstetricians and Gynaecologists' ethics committee, questioned whether is was morally right to be using the science in this way.
"If it gets to the point where we can decide which gene or combination of genes are responsible for blue eyes or blonde hair, what are you going to do with all those other embryos that turn out like me to be ginger with green eyes?"
She warned against "turning babies into commodities that you buy off the shelf."
Josephine Quintavalle of Comment on Reproductive Ethics said: "This is the inevitable slippery slope of a fertility process which results in many more embryos being created than can be implanted. Choices will always have to be made. Do you choose octuplets or the ones with the prettiest noses?"
In the UK, sex selection is banned and choices are currently permitted only in relationship to the baby's health.
Italian fertility law does not permit the creation of surplus embryos or selective testing. Ms Quintavalle said that was "one sure way to avoid the slippery slope".
Meanwhile, new legislation in the UK, due to come in on 6 April, will allow IVF mothers to name anyone as "father" on the birth certificate - even another woman.
The only restriction on naming a second parent will be if they are close blood relatives or if the second person does not agree.
genetics
Saturday, September 13, 2008
Fidelity
In the 1970s, the over-used expression that 'the devil made me do it' was included in everything from television shows to bumper stickers. At least as far as fidelity is concerned, it would now seem to be more appropriate to say 'my genes made me do it'.
***************************************
Men's Fidelity Controlled By Cheating Genetics
Swedish Researchers Say 40 Percent Of Men Possess Gene Linked To Infidelity Among Voles
September 3, 2008
A new study has found similarities in the genetics of cheating rodents and those belonging to men who cheat on their mates.
In the latest tale of mice and men, researchers compared men and voles, a mouse-like varmint.
The study found a gene variant, or allele, present in cheating voles also was present in two of every five men.
According to the study's conclusions, those men with the cheating allele were more prone to marital dysfunction and more likely to get divorced. Men with two copies of the allele were twice as likely as a man without the allele.
The Karolinska Institute in Stockholm, Sweden, studied the genetics of cheating. Researchers there said the cheating allele regulates the activity of a hormone in the brain that can affect a man's attitudes toward fidelity and monogamy.
If a man lacks the gene variant they're more likely to be a devoted mate, researchers said.
Karolinska Institute scientists studied more than 1,000 heterosexual couples. The researchers only looked at men because the hormone produced by the gene is known to play a larger role in men's brains than in women's brains.
The researchers also found that the gene seemed to predict whether women described their mates as close or distant, and whether the men are more likely to marry, or simply live with their mates.
Some people recently told about the study were not completely convinced genetics could govern their relationship fidelity.
"Do I believe that that could be true?" Pat Brawley said. "It certainly could be, but I'd have to see a lot more proof."
Kevin Goldsmith said, "I think it all has to do with your morals and integrity."
At Purchase College in New York, even biology Professor Lee Ehrman, an expert in behavior genetics, was skeptical about the study's results.
"I would not have released this at all if I were in the (public relations) department of the Karolinska," Ehrman said.
However psychologist Glenn Pollack was excited about the news.
"It kept alive that ever famous nature-versus-nurture controversy," Pollack said, "which is one's personal experiences versus one's innate qualities."
Pollack sees the study as a positive tool for proactive marriage counseling, though he warned with follow up studies and future publicity we also could see divorce attorneys using genetics as a defense.
sex
cheating
genes
***************************************
Men's Fidelity Controlled By Cheating Genetics
Swedish Researchers Say 40 Percent Of Men Possess Gene Linked To Infidelity Among Voles
September 3, 2008
A new study has found similarities in the genetics of cheating rodents and those belonging to men who cheat on their mates.
In the latest tale of mice and men, researchers compared men and voles, a mouse-like varmint.
The study found a gene variant, or allele, present in cheating voles also was present in two of every five men.
According to the study's conclusions, those men with the cheating allele were more prone to marital dysfunction and more likely to get divorced. Men with two copies of the allele were twice as likely as a man without the allele.
The Karolinska Institute in Stockholm, Sweden, studied the genetics of cheating. Researchers there said the cheating allele regulates the activity of a hormone in the brain that can affect a man's attitudes toward fidelity and monogamy.
If a man lacks the gene variant they're more likely to be a devoted mate, researchers said.
Karolinska Institute scientists studied more than 1,000 heterosexual couples. The researchers only looked at men because the hormone produced by the gene is known to play a larger role in men's brains than in women's brains.
The researchers also found that the gene seemed to predict whether women described their mates as close or distant, and whether the men are more likely to marry, or simply live with their mates.
Some people recently told about the study were not completely convinced genetics could govern their relationship fidelity.
"Do I believe that that could be true?" Pat Brawley said. "It certainly could be, but I'd have to see a lot more proof."
Kevin Goldsmith said, "I think it all has to do with your morals and integrity."
At Purchase College in New York, even biology Professor Lee Ehrman, an expert in behavior genetics, was skeptical about the study's results.
"I would not have released this at all if I were in the (public relations) department of the Karolinska," Ehrman said.
However psychologist Glenn Pollack was excited about the news.
"It kept alive that ever famous nature-versus-nurture controversy," Pollack said, "which is one's personal experiences versus one's innate qualities."
Pollack sees the study as a positive tool for proactive marriage counseling, though he warned with follow up studies and future publicity we also could see divorce attorneys using genetics as a defense.
sex
cheating
genes
Saturday, April 5, 2008
It's all in the genes
One example might be Gisele Bundchen.
NO DOUBT!
And for your consideration:
Source: INFDaily
But if beauty is genetic and the 1% of the population body is genetic, what else might be genetic.
Naturenews.com has an interesting column on the possibility that ruthlessness is located in a gene. Perhaps Saddam, Hitler, Mugabe, Mobuto, Musolini, Toto, and Tito were all just misunderstood.
NO DOUBT!
And for your consideration:
Source: INFDaily
But if beauty is genetic and the 1% of the population body is genetic, what else might be genetic.
Naturenews.com has an interesting column on the possibility that ruthlessness is located in a gene. Perhaps Saddam, Hitler, Mugabe, Mobuto, Musolini, Toto, and Tito were all just misunderstood.
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