eLife assessment
This study reports the fundamental finding of differential expression of key genes in full-term placenta between Tibetans and Han Chinese at high elevations, which are more pronounced in the placentas of male fetuses than in female ones. If confirmed, these results will help us understand how human populations adapt to high elevation by mitigating the negative effects of low oxygen on fetal growth. However, although the differential gene expression reported is solid, the downstream analyses offer only incomplete support for its connection to hypoxia-specific responses, adaptive genetic variation, and pregnancy outcomes.