For years, older mothers have been blamed for the health problems of their children.
But a study published in Nature today points the finger at older fathers.
An Icelandic company has found that men who father children later in life pass on more new genetic mutations to their offspring than younger dads, possibly increasing their child’s risk of mental disorders such autism and schizophrenia, the Los Angeles Times reported.
Researchers studied the genomes of 78 families in Iceland and found that the number of mutations in a child was related to the age of the father, according to US News.
"Society has been very focused on the age of the mother. But apart from (Down's Syndrome) it seems that disorders such as schizophrenia and autism are influenced by the age of the father and not the mother,” Dr Kari Stefansson, of Decode Genetics, who led the research, was quoted by the BBC as saying.
According to Bloomberg, a 20-year-old man hands about 25 mutations to their offspring, while a 40-year-old man passes on about 65.
Mothers always transmit about 15 new mutations no matter their age, it said.
"The father is an incredibly important contributor to mutations, and even if de novo (new) mutations happen randomly, the more mutations you have, the more likely you will have one in a gene that matters," Stefansson said.
In the United States, one in 88 children had autism or a related disorder in 2008, according to the latest available data from the US Center for Disease Control and Prevention. That is up 23 percent from 2006, Bloomberg reported.
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