Older Men Contribute to Birth of Children with Autism

A father's age has a lot to contribute towards the health of a new born baby. The new study clearly depicts a link between older dads and genetic mutations in children. Older fathers increase the risk of autism, schizophrenia and other disorders when compared to the children of younger dads.

This study was carried in Journal Nature.

It was reported by the U.S Centers for Disease Control and Prevention in Atlanta, Georgia that this year one in every 88 American children has been diagnosed with autism spectrum disorder, which is massive 78 percent increase since 2007.

Autism Spectrum disorder child suffers from a range of complex neurodevelopment disorder that includes social impairments along with communication difficulties, and restricted, repetitive, and stereotyped patterns of behavior. 

According to Wall Street Journal, Kari Stefansson, chief executive officer of deCODE Genetics in Iceland and lead author of the new study said, "It's very likely that the rise in the mean age of fathers has made some contribution to the apparent epidemic of autism in our society."

According to the journal Nature, fathers deliver four times as many new mutations when compared to the mothers. The researchers estimate that a 36 year old have the tendency to transfer twice as many mutations to his child.

The researchers suggest that, even when mutations were not present in either parent and the child carried certain disorder, this would have occurred spontaneously in the egg, sperm or embryo.

 U.S. News quoted Daniel Smith, senior director of discovery neuroscience at Autism Speaks, an autism research and advocacy organization, "This study further establishes that paternal age is a risk factor for [non-hereditary] autism."

For this study Stefansson and his colleagues had studied genomes of 78 trios of father, mother and child. This was done to trace the presence of tiny mutations that occurred in DNA code. Nearly 44 children received a diagnosis of autism spectrum disorder and 21 had schizophrenia. During the course of which they learnt that the average age of fathers residing in Iceland conceiving in 2011 was 33 years, up from 27.9 years in 1980.

Journal Nature quoted Mark Daly, a geneticist at Massachusetts General Hospital in Boston who studies autism, said, "Increasing paternal age is unlikely to account for all the rise in autism prevalence." He notes that autism is highly heritable, but that most cases are not caused by a single new mutation - so there must be predisposing factors that are inherited from parents but are distinct from the new mutations occurring in sperm.

Stefansson concluded saying, "Genetic mutations are the basis for natural selection. You could argue what is bad for the next generation is good for the future of our species."