超級名模和影視紅星如何保持纖細苗條的身材一直是人們津津樂道的話題,，多數(shù)猜測這些公眾人物完美的體型是嚴格節(jié)食的結(jié)果，但是遺傳學(xué)家最新的研究成果給出全新的答案,。遺傳學(xué)家發(fā)現(xiàn)了一種“瘦體”基因，這種基因是由家族里母親的身上遺傳到孩子的體內(nèi)的,。

　　“瘦體”基因是由英國牛津大學(xué)一個由喬-普魯頓教授主持的研究小組發(fā)現(xiàn)的,，這是他們進行線性體DNA研究的一個內(nèi)延擴展部分。牛津大學(xué)的研究人員在對161名母親和她們20歲的子女的DNA進行了檢測,，在這之前研究人員還對他們的體質(zhì)指數(shù)進行了比較,，體質(zhì)指數(shù)是用來衡量體重是否標(biāo)準(zhǔn)的重要尺度，結(jié)果發(fā)現(xiàn),，攜帶“瘦體”基因的女性平均的體質(zhì)指數(shù)為21.9,，而沒有攜帶這種基因的女性平均體質(zhì)指數(shù)為23.5。研究人員表示,，體內(nèi)攜帶這種基因的女性比沒有攜帶此類基因的女性更瘦一些,，而且攜帶“瘦體”基因的女性的孩子更容易從母親那里遺傳到這種基因。普魯頓教授認為攜帶“瘦體”基因的人體內(nèi)新陳代謝進行的更快,，使他們體內(nèi)的脂肪消耗的更快,，而不會貯存在體內(nèi),。據(jù)她的估計，只有大約8%的人攜帶這種基因,。

　　研究結(jié)果顯示，由于“瘦體”基因是從母親那里遺傳的,，因此父親體形對子女體形的形成不會起到太大的作用,，即使父親大腹翩翩，做子女的也不用有絲毫擔(dān)心,，不過父親的某些基因可能會對子女上了年紀后的體重產(chǎn)生一定的影響,。普魯頓教授表示，“瘦體”基因之所以只能從母親那里遺傳,，是因為線性體DNA只能由母親遺傳的結(jié)果,，這也意味著父親的基因在后代體形的形成過程不起太大的作用。

　　這個研究成果或許可以解釋世界上一些極富魅力的女性可以輕而易舉地保持她們優(yōu)美的體型,，比如,，以體型纖細著稱的超級名模納奧米-坎貝爾和凱特-摩斯兩人的母親也都很苗條，美國超級名模杰瑞-夏爾就明顯把她“瘦體”基因遺傳給她同樣在娛樂圈嶄露頭角的女兒伊麗莎白賈格爾,，電視紅星珍西摩爾也把同樣的基因遺傳給了她同樣也是位演員的女兒凱特-弗林,。

　　目前，人們指責(zé)一些超級模特為滿足職業(yè)的要求以節(jié)食來保持體形給年輕的女孩造成了不良的影響,，因此時尚專家這個與以往不同的科學(xué)解釋十分歡迎,，他們表示，這些公眾明星與她們的母親出現(xiàn)在公眾場合時,，人們就會發(fā)現(xiàn)她們母女之間體形的相似之處,，不過如果人們看到明星的母親年輕時的樣子，就會更加吃驚,。

　　普魯頓教授表示,，研究的結(jié)果顯示出母親和她們20歲的子女在體形趨于苗條之間有著緊密的聯(lián)系，但是目前還不清楚這種基因是如何發(fā)揮作用的,，對線性體DNA的研究表明這種基因是由母親遺傳給子女的,。先前的研究結(jié)果顯示，攜帶“瘦體”基因的女性生育的孩子體重更輕,，而且攜帶此類基因的人在上年紀后更易患上2類糖尿病,，特別是攝入過多脂肪時。普魯頓教授表示,，盡管“瘦體”基因能夠使脂肪不易貯存體內(nèi),，但可能會導(dǎo)致子女上了年紀后身體產(chǎn)生其它問題。她表示,，這種基因出現(xiàn)在嬰兒,、兒童和年輕人體內(nèi)時,，能夠使他們的體形變得更瘦，但是在他們長到60歲時就不知道會造成什么后果了,。

　　英國敦提大學(xué)的一位研究肥胖癥的專家表示,，這項研究成果為基因?qū)θ梭w體重的影響提供了新的證據(jù)，這說明線性體DNA對人體能量的平衡起著十分重要的作用,。

THEY may not be starving themselves on a lettuce diet after all. The real secret behind stick-thin supermodels and actresses has been revealed to be their mothers.

Geneticists have discovered a "thinness" gene that is passed down through families from mothers to their children.

The researchers found that women carrying the gene were skinnier than those without it and that their children were also more likely to inherit their mother's slight build if they had the gene.

It may help explain how some of the world's most glamorous women are able to maintain their slimline figures so easily. Superslim models Naomi Campbell and Kate Moss both have skinny mothers. One of the original "supermodels", the statuesque Texan Jerry Hall, appears to have passed on a thinness gene to her daughter Elizabeth Jagger. TV star Jane Seymour appears to have done the same for her actress daughter Katie Flynn.

The researchers claim that because the gene is passed down maternally, fathers - regardless of the size of their beer belly - play little role in determining the body shape of their children, although other paternal factors may influence weight in later life.

The gene was identified by Dr Jo Poulton and her team at the genetics department of Oxford University inside stretches of genetic material responsible for metabolism known as mitochondrial DNA.

Poulton believes people with the gene may have a faster metabolism that allows them to get rid of fat rather than storing it. She estimates that around 8% of the population carry the gene.

"We demonstrated a significant association between the variant and thinness in both mothers and their 20-year-old offspring," said Poulton. "We don't fully understand the mechanisms yet but this mitochondrial DNA seems to pass the likelihood of thinness from mothers to their children. It may explain why families can have several generations of very thin people."

The current generation of top models have been accused of starving themselves into the shape required for the catwalk and providing poor role models for teenage girls. Style experts said they would welcome a different scientific explanation for their look. "Often when you see celebrities with their mothers in public you can see the similarities between their bodies and it is even more striking when you see how their mothers used to look," said Leoni Roberts, from the Federation of Image Consultants. "Naomi Campbell springs to mind as she and her mother, who was a dancer, look so similar they could be sisters.

Former model Freda Bartlet, 40, from Glasgow, believes the research may explain why the women in her family have such a slim build.

Her daughter Haley, 16, has a 23 inch waist and works for Glasgow-based modelling agency Model Team. "When I was Haley's age I used to eat constantly and never put on any weight as I had such a fast metabolism," said Bartlet. "I weighed about seven and a half stone. My mother was exactly the same and now Haley is taking after us. She often wears some of my clothes from when I was younger."

The Oxford study examined the DNA of 161 white, middle-class mothers and their 20-year-old children before comparing the results against their Body Mass Index, a measure of body fat using weight and height. Poulton found that women carrying the gene had an average BMI of 21.9kg/m2 compared with 23.5kg/m2 in those who lacked it.

Earlier research showed that women who carried the gene also gave birth to smaller babies. But Poulton warned that while the gene may protect against getting fat, it may cause other problems in later life.

She said: "When the gene is present in babies, children and young people it seems to confer a thinner physique but we don't yet know what happens when those people get into their sixties.

"Previous research has also found people with this gene have a higher chance of developing type 2 diabetes in later life, particularly if they eat a high fat diet. We think it might be something known as a 'thrifty gene', which was advantageous when food was scarce by allowing more efficient use of food. It can cause problems now food is so abundant all the time."

Poulton also explains that the gene can only be passed down by mothers to their children because mitochondrial DNA is usually only inherited maternally. It means that a father's genetic make-up may play little part in the body-shape of their offspring.

Dr Colin Palmer, an expert on obesity at Dundee University, said the research shed new light on the understanding of how genetics can effect a person's weight. He said: "There have been genes identified for obesity and they are to do with eating behaviour and regulation of appetite. This research seems to come at it from the other angle, but it would make sense as mitochondrial DNA is totally vital to energy balance and how the body adapts to overeating."

A spokesman for the Eating Disorder Association added: "We welcome any research that helps us understand the reasons that lead to people developing eating disorders."

This article: http://news.scotsman.com/scitech.cfm?id=2349862005