Gaur genome reveals expansion of sperm odorant receptors in domesticated cattle

Authors: LOW, WAI - University Of Adelaide; Rosen, Benjamin - Ben; REN, YAN - University Of Adelaide; Bickhart, Derek; TO, THU-HIEN - Norwegian University Of Life Sciences; MARTIN, FERGAL - Collaborator; BILLIS, KONSTANTINOS - Collaborator; SONSTEGARD, TAD - Recombinetics, Inc; SULLIVAN, SHAWN - Phase Genomics, Inc; HIENDLEDER, STEFAN - University Of Adelaide; WILLIAMS, JOHN - University Of Adelaide; Heaton, Michael - Mike; Smith, Timothy - Tim

Submitted to: BMC Genomics
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/13/2022
Publication Date: 5/4/2022
Citation: Low, W.Y., Rosen, B.D., Ren, Y., Bickhart, D.M., To, T., Martin, F.J., Billis, K., Sonstegard, T.S., Sullivan, S.T., Hiendleder, S., Williams, J.L., Heaton, M.P., Smith, T.P. 2022. Gaur genome reveals expansion of sperm odorant receptors in domesticated cattle. BMC Genomics. 23. Article 344. https://doi.org/10.1186/s12864-022-08561-1.
DOI: https://doi.org/10.1186/s12864-022-08561-1

Interpretive Summary: The gaur is the largest wild relative of cattle. Native to South and Southeast Asia, it possesses unique biological traits and is in danger of becoming extinct. We sequenced the genome of the gaur and identified features of its genome that may reflect adaptation to challenges such as climate and nutrition. Through comparisons of the gaur genome to domesticated cattle we were also able to identify signals of artificial selection in cattle. These signals included an expansion of sperm odorant receptor genes in domesticated cattle, which may have important implications for understanding male fertility. The new genome assembly will aid in the dissection of economically important traits and also provide the foundation to conservation efforts in the species.

Technical Abstract: The gaur (Bos gaurus) is the largest extant wild bovine species, native to South and Southeast Asia and listed as vulnerable by the IUCN. The species has unique traits, including secretion of an oily substance called bovidic acid that functions as an insect repellent. We report the first gaur reference genome and identify three biological pathways including lysozyme activity, proton transmembrane transporter activity, and oxygen transport with significant changes in gene copy number in gaur compared to other mammals. These may reflect adaptation to challenges related to climate and nutrition. Comparative analyses with domesticated indicine (Bos indicus) and taurine (Bos taurus) cattle revealed genomic signatures of artificial selection, including the expansion of sperm odorant receptor genes in domesticated cattle, which may have important implications for understanding selection for male fertility. Apart from aiding dissection of economically important traits, the gaur genome will also provide the foundation to conserve the species.