Risk comes from older fathers, not mothers

“We have shown how new mutations come much more often from the father than from the mother,” says Kári Stefánsson, CEO of DeCode Genetics.

“A child conceived by a forty-year-old father passes on to his offspring twice as many new mutations as one conceived by a twenty-year-old father. It so happens that the risk of autism is two to three times greater in a child conceived by a forty-year-old father than in a twenty-year-old. The risk of schizophrenia is considerably greater in a child conceived by a forty-year-old father than in a twenty-year-old father. Childhood cancers are, thank God, rare, but they are greatly influenced by these new mutations.”

Stefánsson is in an in-depth interview in Tímamót, the year-end issue of Morgunblaðið, where he discusses the company’s research and more.

He says that when he was in medical school, students were taught that the mother's advanced age was a major risk to the child.

"It turns out that the father's advanced age is much more dangerous. When you look at the fate of children according to the mother's age at birth, there is probably nothing better for a child than being born to an older mother.

A child born to an older mother is an individual who is more educated, has a much lower risk of addiction and a much lower risk of cardiovascular disease. So it's all been turned around. The older father is the big risk," says Kári Stefánsson in the interview.