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Children of older fathers have increased chances of autism, schizophrenia

A study shows a 70-year-old man will pass on eight times as many genetic mutations to his child than a 20-year-old.

Image: furiousmadgeorge via Flickr

A NEW STUDY found that older men may be more likely to father children who develop autism or schizophrenia than young dads.

The study, published in Nature, found that men fathering children in their thirties and forties could be increasing the chances that their children will develop diseases linked to new mutations.

Kári Stefánsson, lead author of the article, said the older a man is when he fathers a child, the more likely he is to pass on mutations and so the greater the chances that one of them will be harmful.

Previous research had already shown that fathers were more likely to pass on genetic mutations than mothers because sperm are made throughout a man’s lifetime while women are born with their lifelong supply of egg cells.

The study found that men pass on nearly four times as many mutations as women to their children with fathers’ ages accounting for nearly all of the difference in the number of mutations passed on.

Stefánsson’s research team estimates a 36-year-old will pass on twice as many mutations to his child as a man of 20 while a 70-year-old will pass on eight times as many.

Most mutations are harmless but the research team have linked to conditions such as autism and schizophrenia. While the study does not prove outright that older men are more likely to pass on dangerous mutations to their children, Stefánsson said that is the strong implication.

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