Older fathers have uglier children, researchers have claimed after linking age to genetic mutations . The finding comes weeks after leading scientists reported children born to men over the age of 45 run a higher risk of having autism and mental disorders. With age, sperm -producing cells do not copy a man's DNA as effectively, leading to genetic mutations. Martin Fielder, an anthropologist  at Vienna University, told the Sunday Times: 'Every 16 years the mutation rate doubles. Other researchers found 25 mutations per sperm in a 20-year-old, but at age 40 it is 65 mutations. By 56, it doubles again. The effect is very visible - someone born to a father of 22 is already 5-10 per cent more attractive than those with a 40-year-old father and the difference grows with the age gap. In contrast, women pass on a maximum of 15 mutations to their baby, regardless of age, according to the study published in the journal Nature. Surveying a group of six men and six women, researchers showed them each 4,018 photographs of 18-20-year-old men and 4,416 of women the same age, and asked to assess their attractiveness. Those with older fathers were consistently considered less attractive. However, the children of older men, though less attractive, are likely to outlive their peers with younger fathers, it is claimed. Professor Lee Smith, a geneticist at Edinburgh University, told the Sunday Times other research found such children have longer telomeres  - the caps on the end of chromosomes --- which are associated with longer life. But the mounting research connecting parents' age with autism is cause for concern, experts warn. Autism is an umbrella term for a range of developmental disorders that have a lifelong effect on someone's ability to interact socially and communicate openly. In the UK, around one in 100 adults is thought to be affected by autism, mostly men, caused by a combination of genetic and environmental factors. Researchers said men should be advised about the potential problems in order to help their personal decision-making when it came to having fathering children at older ages. They warned that advancing paternal age faced a risk of 'numerous public health and societal problems'. Among well-known older dads are Simon Cowell, 54, whose son was born earlier this month, and comedian Frank Skinner whose first child was born in 2012 when he was 55. The whole passage is developed mainly by means of   _  .
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