title: Major histocompatibility complex class II genetic variation in forest musk deer (Moschus berezovskii) in China.
abstract: The major histocompatibility complex (MHC) plays an important role in the immune system of vertebrates. We used the second exon of four MHC class II genes (DRA, DQA1, DQA2 and DRB3) to assess the overall MHC variation in forest musk deer (Moschus berezovskii). We also compared the MHC variation in captive and wild populations. We observed 22 alleles at four loci (four at DRA, four at DQA1, four at DQA2 and 10 at DRB3), 15 of which were newly identified alleles. Results suggest that forest musk deer maintain relatively high MHC variation, which may result from balancing selection. Moreover, considerable diversity was observed at the DRA locus. We found a high frequency of Mobe-DRA*02, Mobe-DQA1*01 and Mobe-DQA2*05 alleles, which may be important for pathogen resistance. A Ewens-Watterson test showed that the DRB3 locus in the wild population had experienced recent balancing selection. We detected a small divergence at the DRA locus, suggesting the effect of weak positive selection on the DRA gene. Alternatively, this locus may be young and not yet adapted a wide spectrum of alleles for pathogen resistance. The significant heterozygosity deficit observed at the DQA1 and DRB3 loci in the captive population and at all four loci in the wild population may be the result of a population bottleneck. Additionally, MHC genetic diversity was higher in the wild population than in the captive, suggesting that the wild population may have the ability to respond to a wider range of pathogens.
authors.affiliation: The Key Laboratory of Conservation Biology for Endangered Wildlife of the Ministry of Education, and State Conservation Centre for Gene Resources of Endangered Wildlife, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China.
authors.forename: Gang
authors.initials: G
authors.lastname: Yao
authors.affiliation: The Key Laboratory of Conservation Biology for Endangered Wildlife of the Ministry of Education, and State Conservation Centre for Gene Resources of Endangered Wildlife, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Zhu
authors.affiliation: The Key Laboratory of Conservation Biology for Endangered Wildlife of the Ministry of Education, and State Conservation Centre for Gene Resources of Endangered Wildlife, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China.
authors.forename: Qiu-Hong
authors.initials: QH
authors.lastname: Wan
authors.affiliation: The Key Laboratory of Conservation Biology for Endangered Wildlife of the Ministry of Education, and State Conservation Centre for Gene Resources of Endangered Wildlife, College of Life Sciences, Zhejiang University, Hangzhou, 310058, China.
authors.forename: Sheng-Guo
authors.initials: SG
authors.lastname: Fang
mesh_terms: D000483:Alleles; D000818:Animals; D002681:China; D003670:Deer / Q000235:genetics*; D005091:Exons; D005802:Genes, MHC Class II / Q000235:genetics*; D014644:Genetic Variation; D005828:Genetics, Population; D005838:Genotype; D008969:Molecular Sequence Data; D010802:Phylogeny; D012641:Selection, Genetic; D017422:Sequence Analysis, DNA
keywords: DRA diversity; antigen-binding sites; balancing selection; heterozygosity deficit; positive selection