Scientists don't debate the old nature vs. nurture question much these days. The consensus is that there is no winner: Both your genes and your environment shape your development and your health. What's still up in the air is how they combine to put you at risk for diseases or social problems. And that matters for people trying to solve them.
Now it appears that, even for a single disease or condition, the balance between nature and nurture isn't fixed place to place. That's what researchers at Kings College London, writing this week in the journal Molecular Psychiatry, are showing with maps that identify hotspots in the U.K. where either genetic or environmental factors dominate.
"Virtually everything you can measure is a mix of genes and the environment," Oliver Davis, a lecturer in psychiatry and lead author of the study, tells Shots. "What we're interested in here is how that balance shifts in different places."
The data comes from the Twins Early Development Study, which has followed more than 5,000 pairs of twins from birth over the last 16 years. Researchers tracked a number of factors for each child, including school performance, behavior problems, mood and attention disorders, and weight. By comparing the variation between children with genetic differences, they were able to figure out how genes and environment relate to each factor.
When they plotted the data on a map, they saw clear geographic patterns. "You can see areas where the variation is explained by genes, and areas where it's explained by the environment," says Davis.
In some areas, Davis says, "the environment is such that it draws out the genetic differences between people." In other places, it appears that environmental factors overpower the influence of genes.
For instance, the researchers found that variation in classroom behavior between kids was better explained by environmental factors in London. It also seemed to match the higher variation in incomes in London; they saw this when they compared their map to a map of income inequality.
It's not enough to prove that high income inequality directly influences classroom behavior, but it suggests directions for future research.
Davis says the maps will help experts to figure out who might be at risk, and then mitigate those risks. "The really cool thing about doing it visually like this is it makes it easy to bring in experts from a variety of fields," he says.
The maps may not be very useful to the general public – but they are pretty. If you're so inclined, you can download an interactive version as a software package from the Twins Early Development Study website.