The largest study to date investigating the genetic underpinnings of intelligence suggests there is, in fact, a link between wearing glasses (or contact lenses) and cognitive function, with intelligent people almost 30 percent more likely to be glasses wearers. "This study, the largest genetic study of cognitive function, has identified many genetic differences that contribute to the heritability of thinking skills," says genetic statistician Gail Davies from the University of Edinburgh in the UK.
Davies and her team combed through the genetic information of over 300,000 individuals compiled from existing genomic databases, in which participants submitted samples for DNA analysis, answered questionnaires, and underwent tests designed to give a measure of their general cognitive ability.
When they analysed the genetic data, the researchers discovered 148 genome-wide regions associated with general cognitive function, including 58 genomic sites that hadn't previously been linked with intelligence. They also found 42 genome-wide loci linked to reaction time, 40 of which are new to science.