Sibling Decomposition Reveals SES in PGS

This study shows that for intelligence and education, roughly half of polygenic‑score prediction in the population comes from between‑family differences (ancestry, mating, household) rather than within‑family genetic differences, and that socioeconomic status explains much of that between‑family portion. Using dizygotic twin differences and unrelated individuals in the UK Twins Early Development Study (N≈10,000), the authors contrast within‑family vs population PGS prediction across development. — It reframes PGS findings from being taken as straightforward evidence of individual genetic determinism to being context‑dependent signals that embed family environment and social inequality, affecting education policy, genetics communication, and ethical uses of PGS.