However, they also discovered this does not seem to be driving changes in the gene pool.
‘While there is a tendency for people who are genetically similar along key dimensions to marry each other, there does not seem to be any increase in this tendency, despite what some people may fear about inequality getting baked into our genes,’ said Dalton Conley, a professor of sociology, medicine and public policy at New York University and author of the study.
‘Ditto for how many kids folks are having – while there are genetic associations, they appear to be stable over time.’
The researchers wanted to find of the gene pool was being affected – for instance, in a scenario where tall people have a propensity to marry each other and have many children, while short people likewise married but had fewer children.
If we assume that the height of these people reflects the influence of their DNA, one might expect to see more genes for tallness in the population over time.
‘As we get better and better measures of genotypes with bigger and bigger subject pools, it will be important to reproduce this study to keep tabs on how social forces – like rising income inequality or changing marriage norms – may be affecting us at the population genetics level,’ Conley said.