Genetics: Investigating how yaks adapt to low oxygen environments

Insights into the genetic and cellular adaptations that enable yak to survive at high altitudes are presented in a paper published in Nature Communications. The findings identify an endothelial lung cell, specific to yaks, that may play a role in their ability to survive in low oxygen environments.

Domestic yak (Bos grunniens) and wild yak (Bos mutus) inhabit high altitude regions (3,000–6,000 metres above sea level) in the Tibetan Plateau, which are characterised by low oxygen concentrations. Non-native mammals, including humans, can experience serious lung and heart issues following exposure to low oxygen conditions. However, this is not the case for wild and domestic yaks, which have adapted to low oxygen conditions over millions of years.

To explore how yaks are adapted to these environments, Qi-En Yang and colleagues combined genomic and transcriptomic data to present a high-quality genome assembly for domestic and wild yak, as well as a map of the different lung cell types. They identified 127 genes that were expressed differently in yaks compared to European cattle and identified an endothelial cell subtype that is only found in yak lung tissue. This yak-specific cell type was shown to express genes potentially involved in high altitude adaptation.

The authors conclude that their findings provide insights into the genetic adaptations of yaks to high altitude environments and may have implications for our understanding of different responses to low oxygen environments in other mammals.