Scientists have achieved a breakthrough in deciphering the genetics of intelligence. Ironically, they did it by accounting for a key environmental factor.
Breast-feeding boosts children's IQs by 6 to 7 points over the IQs of kids who weren't breast-fed, but only if the breast-fed youngsters have inherited a gene variant associated with enhanced chemical processing of mothers' milk, reports a team led by psychologist Avshalom Caspi of King's College London.
The new finding supports the controversial hypothesis that fatty acids in breast milk enhance newborn babies' brain development. Moreover, the results demonstrate that intelligence researchers must examine how children's genetic natures interact with the ways in which they're nurtured.
"Genes work via specific environmental experiences to shape intellectual development," Caspi says.
He and his colleagues present their data in an upcoming Proceedings of the National Academy of Sciences.