Each mutation contributed only a small amount. In terms of the year of schooling, one copy of the SNP meant that an individual completed I month of additional schooling.(Each person can have up to two copies of an individual SNP , one from mom and one from dad.)
For college completion. The most indicative SNP corresponded to a 1.8 percentage-point rise in the likelihood of graduating from college. IF a person had two copies of this SNP , then, their likelihood would rise by 3.6 point
These are small effects but meaningful because they held up on such a large scale. The findings support the general consensus that our behavioral traits are influenced by a large number of genes, each of small effect. Overall, each SNP in this study altered educational attainment by only about 0.02%. In comparison, for a complex physical trait like human height, a single SNP can influence the outcome by 0.4%
Ongoing genetic research keeps reinforcing this idea that genes aren’t destiny – there’s no gene for graduating college. But it’s good to keep in mind that genes are part of the list of contributors that make us who we are