Individuals with genes for high educational achievement tend to marry, and have children with people with similar DNA, experts have found.
Humans generally do not choose their partners randomly, but rather mate 'assortatively', choosing people with similar traits.
Among the highest ranking qualities people look for in a potential partner are intelligence and educational attainment, the study published in the journal Intelligence said, adding that the choice has a significance at a DNA level.
‘Assortative mating pattern could increase genetic and social inequality in future generations, since children of such couples are more unequal genetically than those of people who mate more randomly.’
"Our findings show strong evidence for the presence of genetic assortative mating for education. The consequences of assortative mating on education and cognitive abilities are relevant for society, and for the genetic make-up and therefore the evolutionary development of subsequent generations," said David Hugh-Jones, lecturer at University of East Anglia (UEA) in Britain.
However, assortative mating pattern could increase genetic and social inequality in future generations, since children of such couples are more unequal genetically than those of people who mate more randomly, the researchers argued.
"Assortative mating on inheritable traits that are indicative of socio-economic status, such as educational achievement, increases the genetic variance of characteristics in the population. This may increase social inequality, for example with respect to education or income," Hugh-Jones added.
"When growing social inequality is, partly, driven by a growing biological inequality, inequalities in society may be harder to overcome and the effects of assortative mating may accumulate with each generation," Hugh-Jones said.
For the study, the team examined approximately 1,600 married or cohabiting couples in Britain. They used polygenic scores that predict educational attainment to see whether they predicted the partner's own educational attainment and polygenic score.
The results showed that the individuals with a stronger genetic predisposition for higher educational achievement have partners who are more educated.