title: Patterns of genetic differentiation at MHC class I genes and microsatellites identify conservation units in the giant panda.
abstract: BACKGROUND
  Evaluating patterns of genetic variation is important to identify conservation units (i.e., evolutionarily significant units [ESUs], management units [MUs], and adaptive units [AUs]) in endangered species. While neutral markers could be used to infer population history, their application in the estimation of adaptive variation is limited. The capacity to adapt to various environments is vital for the long-term survival of endangered species. Hence, analysis of adaptive loci, such as the major histocompatibility complex (MHC) genes, is critical for conservation genetics studies. Here, we investigated 4 classical MHC class I genes (Aime-C, Aime-F, Aime-I, and Aime-L) and 8 microsatellites to infer patterns of genetic variation in the giant panda (Ailuropoda melanoleuca) and to further define conservation units.
  
  
  RESULTS
  Overall, we identified 24 haplotypes (9 for Aime-C, 1 for Aime-F, 7 for Aime-I, and 7 for Aime-L) from 218 individuals obtained from 6 populations of giant panda. We found that the Xiaoxiangling population had the highest genetic variation at microsatellites among the 6 giant panda populations and higher genetic variation at Aime-MHC class I genes than other larger populations (Qinling, Qionglai, and Minshan populations). Differentiation index (FST)-based phylogenetic and Bayesian clustering analyses for Aime-MHC-I and microsatellite loci both supported that most populations were highly differentiated. The Qinling population was the most genetically differentiated.
  
  
  CONCLUSIONS
  The giant panda showed a relatively higher level of genetic diversity at MHC class I genes compared with endangered felids. Using all of the loci, we found that the 6 giant panda populations fell into 2 ESUs: Qinling and non-Qinling populations. We defined 3 MUs based on microsatellites: Qinling, Minshan-Qionglai, and Daxiangling-Xiaoxiangling-Liangshan. We also recommended 3 possible AUs based on MHC loci: Qinling, Minshan-Qionglai, and Daxiangling-Xiaoxiangling-Liangshan. Furthermore, we recommend that a captive breeding program be considered for the Qinling panda population.
authors.forename: Ying
authors.initials: Y
authors.lastname: Zhu
authors.forename: Qiu-Hong
authors.initials: QH
authors.lastname: Wan
authors.forename: Bin
authors.initials: B
authors.lastname: Yu
authors.forename: Yun-Fa
authors.initials: YF
authors.lastname: Ge
authors.affiliation: The Key Laboratory of Conservation Biology for Endangered Wildlife of the Ministry of Education, State Conservation Centre for Gene Resources of Endangered Wildlife, College of Life Sciences, Zhejiang University, No, 388 Yu Hang Tang Road, Hangzhou 310058, PR China. sgfanglab@zju.edu.cn.
authors.forename: Sheng-Guo
authors.initials: SG
authors.lastname: Fang
mesh_terms: D000818:Animals; D001499:Bayes Theorem; D002681:China; D056727:Endangered Species; D005805:Genes, MHC Class I; D014644:Genetic Variation; D005828:Genetics, Population; D006239:Haplotypes; D018895:Microsatellite Repeats; D010802:Phylogeny; D001503:Ursidae / Q000235:genetics*