I’ve always wondered what kind of influence that our genetics have on intelligence because I’ve personally thought that intelligence was mostly a learned behavior. After reading these two articles it is apparent that yes, genetics plays a role in intelligence; in fact, it is thought to be around 50-80% of the variation in general intelligence is due to genetics. When comparing DNA variants from more than 240,000 people in the UK, researchers found 538 genes linked to intellectual ability and 187 regions of the human genome that are associated with thinking skills. Furthermore, another article states that another study found 22 genes accounted for about 5% of the differences in intelligence scores. Some of these genes are also associated to other biological processes such as living longer as well. However, even though these genes were found to be linked to intelligence, when researchers were trying to predict intelligence differences between two different people they were only able to predict about 5-7% of the intelligence differences as a whole. This reinforces the fact that environmental factors have a significantly larger influence on intelligence than genes do: for example, proper nourishment is vital and the article even states that deprived children receive lower IQ scores. Overall, I was actually shocked that they found such a minute amount of genetics linked to intelligence and that environmental factors dominates within this area. When putting it into perspective people contain around 200,000 total genes and only having roughly 538 of those genes be linked to intelligence is pretty insignificant when it’s such an important factor. Even more shocking, the fact that 538 genes only account for 5-7% of intelligence differences as a whole is very insignificant as well.
This topic was fascinating to learn about how not just environmental factors contribute to our intellectual intelligent, but there are also a few percentages of genes that contribute to it as well. I agree with you about the proper way that you say "nourishment is vital" as the vital factor that contributes to intelligent.