An international team of genetic scientists has completed the genomic sequence of the Tibetan antelope (Pantholops hodgsonii).
Tibetan antelope, or chiru, in the Chang Tang region of Tibet (George Schaller)
The Tibetan antelope, also known as chiru, is a native of the high mountain steppes and semi-desert areas of the Tibetan plateau. It is a medium sized antelope with the unique adaptations to against the harsh high-altitude climate.
The Tibetan antelope, the only member of the genus Pantholops, can live at elevations of 2.5 – 3.1 miles (4 – 5 km).
The scientists suggest that Tibetan antelopes must have evolved exceptional mechanisms to adapt to this extremely inhospitable habitat. They have decoded the genome of Tibetan antelope and studied the underlying genetic mechanism of high-altitude adaptations.
Through the comparison between Tibetan antelope and other plain-dwelling mammals, researchers found the Tibetan antelope had the signals of adaptive evolution and gene-family expansion in genes associated with energy metabolism and oxygen transmission, indicating that gene categories involved in energy metabolism appear to have an important role for Tibetan antelope via efficiently providing energy in conditions of low partial pressure of oxygen.
Further research revealed that both the Tibetan antelope and the highland American pika have signals of positive selection for genes involved in DNA repair and the production of ATPase.
Considering the exposure to high levels of ultraviolet radiation, positive selective genes related to DNA repair may be vital to protect the Tibetan antelope from it.
“The completed genome sequence of the Tibetan antelope provides a more complete blueprint for researchers to study the genetic mechanisms of highland adaptation,” explained Dr Qingle Cai from the BGI-Shenzhen, co-author of the study published in Nature Communications.
“This work may also open a new way to understand the adaptation of the low partial pressure of oxygen in human activities.”
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Bibliographic information: Ri-Li Ge et al. Draft genome sequence of the Tibetan antelope. Nature Communications 4, article number: 1858; doi: 10.1038/ncomms2860
