title: Identification of MHC I class genes in two Platyrrhini species.
abstract: The major histocompatibility complex is a diverse gene family that plays a crucial role in the adaptive immune system. In humans, the MHC class I genes consist of the classical loci of HLA-A, -B, and -C, and the nonclassical loci HLA-E, -F, and -G. In Platyrrhini species, few MHC class I genes have been described so far and were classified as MHC-E, MHC-F, and MHC-G, with MHC-G possibly representing a classical MHC class I locus while there were arguments about the existence of the MHC-B locus in Platyrrhini. In this study, MHC class I genes were identified in eight common marmosets (Callithrix jacchus) and two brown-headed spider monkeys (Ateles fusciceps). For common marmosets, 401 cDNA sequences were sequenced and 18 alleles were detected, including 14 Caja-G alleles and 4 Caja-B alleles. Five to eleven Caja-G alleles and one to three Caja-B alleles were detected in each animal. For brown-headed spider monkeys, 102 cDNA sequences were analyzed, and 9 new alleles were identified, including 5 Atfu-G and 4 Atfu-B alleles. Two or three Atfu-G and two Atfu-B alleles were obtained for each of animal. In phylogenetic analyses, the MHC-G and -B alleles from the two species and other Platyrrhini species show locus-specific clusters with bootstrap values of 86% and 50%. The results of pairwise sequence comparisons and an excess of non-synonymous nucleotide substitutions in the PBR region are consistent with the suggestion that Caja-G and Atfu-G may be classical MHC class I loci in the Platyrrhini species… But it appears that MHC-B locus of the two Platyrrhini species shares features with both classical and nonclasical MHC class I loci. Our results are an important addition to the limited MHC immunogenetic information available for the Platyrrhini species.
authors.affiliation: Laboratory Animal Center of the Academy of Military Medical Science, Beijing, China; College of Life Sciences of Tarim University, Alaer, China.
authors.forename: Yu-Hua
authors.initials: YH
authors.lastname: Cao
authors.forename: Jun-Wen
authors.initials: JW
authors.lastname: Fan
authors.forename: Ai-Xue
authors.initials: AX
authors.lastname: Li
authors.forename: Hui-Fang
authors.initials: HF
authors.lastname: Liu
authors.forename: Lian-Rui
authors.initials: LR
authors.lastname: Li
authors.forename: Cheng-Lin
authors.initials: CL
authors.lastname: Zhang
authors.forename: Lin
authors.initials: L
authors.lastname: Zeng
authors.forename: Zhao-Zeng
authors.initials: ZZ
authors.lastname: Sun
mesh_terms: D000483:Alleles; D000595:Amino Acid Sequence; D000818:Animals; D053819:Atelinae / Q000235:genetics*; D002144:Callithrix / Q000235:genetics*; D019143:Evolution, Molecular; D005805:Genes, MHC Class I; D008969:Molecular Sequence Data; D010802:Phylogeny; D016415:Sequence Alignment
keywords: Ateles; Callithrix; immune genes; marmoset; new world primate; spider monkey