Higher oxygen content and transport characterize high-altitude ethnic Tibetan women with the highest lifetime reproductive success

作者：Shenghao Ye, Jiayang Sun, Sienna R. Craig, Anna Di Rienzo, David Witonsky, James J. Yu, Esteban A. Moya, Tatum S. Simonson, Frank L. Powell, Buddha Basnyat, Kingman P. Strohl, Brian D. Hoit, Cynthia M. Beall · 发表于：Proceedings of the National Academy of Sciences · 年份：2024 · DOI：10.1073/pnas.2403309121 · 被引用次数：16 · 研究领域：High Altitude and Hypoxia、Birth, Development, and Health、Pregnancy and preeclampsia studies

We chose the “natural laboratory” provided by high-altitude native ethnic Tibetan women who had completed childbearing to examine the hypothesis that multiple oxygen delivery traits were associated with lifetime reproductive success and had genomic associations. Four hundred seventeen (417) women aged 46 to 86 y residing at ≥3,500 m in Upper Mustang, Nepal, provided information on reproductive histories, sociocultural factors, physiological measurements, and DNA samples for this observational cohort study. Simultaneously assessing multiple traits identified combinations associated with lifetime reproductive success measured as the number of livebirths. Women with the most livebirths had distinctive hematological and cardiovascular traits. A hemoglobin concentration near the sample mode and a high percent of oxygen saturation of hemoglobin raised arterial oxygen concentration without risking elevated blood viscosity. We propose ongoing stabilizing selection on hemoglobin concentration because extreme values predicted fewer livebirths and directional selection favoring higher oxygen saturation because higher values had more predicted livebirths. EPAS1, an oxygen homeostasis locus with strong signals of positive natural selection and a high frequency of variants occurring only among populations indigenous to the Tibetan Plateau, associated with hemoglobin concentration. High blood flow into the lungs, wide left ventricles, and low hypoxic heart rate responses aided effective con...