New UK research suggests that older fathers have sons who are more intelligent, more focused on their own interests, and less concerned with fitting in at school, helping to give them an educational boost.
Carried out by a team from King's College London along with The Seaver Autism Center for Research and Treatment at the Icahn School of Medicine at Mount Sinai in the USA, the large-scale study looked at behavioral and cognitive data from 15,000 UK-based twin pairs in the Twins Early Development Study (TEDS).
At age 12, participants were asked to complete online tests that measured what the team called 'geek-like' traits, including non-verbal IQ, a strong focus on a subject of interest and levels of social aloofness.
Parents were also asked whether their child cared about how they are perceived by their peers, and if they had any interests which took up a large portion of their time.
The researchers found that sons of older fathers were more likely to demonstrate the "geek-like" traits, care less about what their peers thought of them, and spend more time on their special interests.
In addition, they also found that they performed better in school exams, particularly in STEM (science, technology, engineering and mathematics) subjects, even several years after study finished.
This results also still held even after the team took into account parents' social/economic status, qualifications and employment.
Although previous research has found that older fathers have children with a higher risk of negative health outcomes, including autism and schizophrenia, the new study suggests that children with older dads may have some advantages when it comes to education and career.
The study did not look directly into how environmental factors play a role, but the team did put forward some suggestions.
As older fathers are more likely to have established their careers and have a higher socioeconomic status than younger fathers, their children may be brought up in more enriched environments and have access to better schooling.
The team also hypothesized that there is a genetic link between older paternal age, autism, and the personality traits found in the study, suggesting that some of the genes for the "geek-like" traits and for autism are overlapping, and that those genes are more likely to be present in older fathers.
"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," explained Dr Magdalena Janecka from King's College London and The Seaver Autism Center at Mount Sinai.
The findings can be found published online in the journal Translational Psychiatry.