question: Which genes are responsible for the high-altitude adaptation of Tibetans?
answer: Recent studies have identified genes involved in high-altitude adaptation in Tibetans. Genetic variants/haplotypes within regions containing three of these genes (EPAS1, EGLN1, and PPARA) are associated with relatively decreased hemoglobin levels observed in Tibetans at high altitude, providing corroborative evidence for genetic adaptation to this extreme environment.  A gene (HMOX2) involved in heme catabolism, harbors potentially adaptive variants in Tibetans.