Adaptations in human populations at high altitude
Signals of genetic adaptation to high altitude that our group and others recently identified are among the strongest in the human genome. Several of these genetic factors are related to oxygen sensing and response and are linked to important physiological traits. Some of these selection candidate genes (e.g., EPAS1
) are specifically associated with relatively lower hemoglobin concentration in Tibetan populations, and the direct targets of these adaptative events are studied by our research team. Our studies of Andean highlanders suggest some of these same genetic pathways exhibit similar adaptive signatures, yet many of the potentially functional variants appear to be different, which supports idea that these populations have adapted to the environmental stress of hypoxia in different ways.
Our current work aims to determine: 1) the physiological relevance of hemoglobin concentration in high-altitude populations, 2) whether physiological variation (e.g., exercise capacity, specific oxygen transport components, intermittent hypoxia during sleep) are related to epigenetic and/or adaptive genetic factors, and 3) how these evolutionary insights relate to natural variation and health and disease in other populations.