LONDON • Research has found that older men tend to have sons who are more aloof, more intelligent, more focused on their interests and less concerned about fitting in - characteristics typically seen in "geeks".
While past research has shown that children of older fathers are at higher risk of some adverse outcomes such as autism, this study of nearly 8,000 British twins by King's College London shows there may be benefits as well. The finding suggests having an older father may boost children's performance in technical subjects at secondary school, reported The Guardian.
Researchers in Britain and the US analysed questionnaires from 7,781 British twins and scored them according to their non-verbal IQ at age 12, and parental reports on how focused and socially aloof they were. The scientists then combined these scores into an overall "geek index".
Dr Magdalena Janecka at King's College London said the project came about after she and her colleagues had brainstormed what traits and skills helped people to succeed in the modern age. "If you look at who does well in life right now, it's geeks," she told The Guardian.
Drawing on the twins' records, the scientists found that children born to older fathers tended to score slightly higher on the geek index.
For a father aged 25 or younger, the average score of the children was 39.6. This rose to 41 in children with fathers aged 35 to 44, and to 47 for those with fathers aged over 50.
The effect was strongest in boys, where the geek index rose by about 1.5 points for every extra five years of paternal age. The age of the children's mothers seemed to have almost no effect on the geek index.
This effect persisted after controlling for parents' socio-economic status, qualifications and employment. Also, it was found that "geekier" children did better in exams, particularly in the Stem (science, technology, engineering and mathematics) subjects, several years after their geek index was measured.
Overall, children born when their fathers were 50 or older were 32 per cent more likely to achieve two A or A* grades at the General Certificate of Secondary Education exams than children born to men aged under 25.
Dr Janecka said the study is one of the first to suggest that having an older father can have benefits for a child, reported The Guardian.
The scientists calculate that 57 per cent of the geek index score is inherited, but this is likely to vary with age. If right, it suggests DNA and the environment have roughly an equal share in how geeky someone turns out. Writing in the journal, they speculated there may be some overlap with genes that contribute to autism and a high score on their index.
If the findings are right, it is unclear why the effect is different in girls. Dr Janecka said the study may simply have failed to capture how girls display geekiness: "They may be geeky in a different way to boys."
But it is also possible that what averts autism in girls - five times as many males are diagnosed - shields them from the most geeky traits.
According to Science Daily, the results have implications for understanding links between higher paternal age, autism and characteristics seen in "geeks". Although the researchers could not measure it directly, they hypothesize that some genes for geekiness and for autism overlap, and those genes are more likely to be present in older fathers.
Dr Janecka said: "When the child is born only with some of those genes, they may be more likely to succeed in school. However, with a higher 'dose' of these genes, and when there are other contributing risk factors, they may end up with a higher predisposition for autism. This is supported by recent research showing that genes for autism are also linked with higher IQ."