New York, May 2 (IANS): A father's age at the time of his children's birth may influence their social development, behaviour including conduct and peer problems, hyperactivity and emotional quotient, a study suggests.

"Our study suggests that social skills are a key domain affected by paternal age," said Magdalena Janecka, doctoral candidate at the Icahn School of Medicine in New York City.

"What was interesting is that the development of those skills was altered in the children of both older as well as very young fathers," Janecka added.

"In extreme cases, these effects may contribute to clinical disorders. Our study, however, suggests that they could also be much more subtle," the study said.

The researchers found that children born to very young and older fathers -- below 25 and over 51 years of age, respectively -- showed more prosocial behaviours in early development.

But, by the time they reached adolescence, they lagged behind their peers who had middle-aged fathers.

These findings may offer insights into how paternal age influences children's risk of autism and schizophrenia, which was shown in earlier studies, the researchers said, in the paper published in the Journal of the American Academy of Child and Adolescent Psychiatry (JAACAP).

"Our results suggests that children born to very young or older fathers may find social situations more challenging, even if they do not meet the diagnostic criteria for autism," Janecka said.

Further, development of social skills was found to be influenced predominantly by genetic rather than environmental factors and that those genetic effects became even more important as the paternal age increased.

However, these effects were specific to the social domain and were not observed in relation to maternal age, the researchers stated.

For the study, Janecka and her team used a British-based sample of more than 15,000 twins, who were followed between the ages of 4 and 16.