关键词: HBK 鸭, 主要组织相容性复合体经典 I 类分子, 无特定病原体, 微卫星标记

Abstract: Abstract: Avian major histocompatibility complex ( MHC) gene family is a cluster of closely linked and highly polymorphic gene groups that are closely associated with immune response or sensibility． Duck MHC I region has a length of 36. 8 kb，including TAP1，TAP2 and five MHC I gene copies ( UAA ～ UEA) ． Two strains，B and Q，of the HBK-SPF ( specific pathogen free ) duck have been bred to the seventh generation in Harbin Veterinary Ｒesearch Institute of Chinese Academy of Agricultural Sciences． Four microsatellite loci were screened in the MHC I region and polymorphism was detected through the single-strand conformation polymorphism，the polymerase chain reaction ( PCＲ) and the directly sequencing． The A locus was found to be polymorphic and characterized by the repeat motif of ( GT) n ． In both the HBK-B and the HBK-Q strains，31 and 140 individuals of the sixth and the seventh generations respectively were detected by the PCＲ and the directly sequencing，and four homozygous and six heterozygous genotypes were found in the upstream 108 bp sequence of the ( GT) n ; There were no PCＲ product at the B locus; PCＲ product of locus C was highly homologous to the corresponding region between the UAA and the UBA genes，and the genotype of locus C could not be identified; locus D was monomorphic，and characterized by the repeat motif of ( ATA) 15 ． This study provides useful data for further research on duck MHC I genome and family establishment．

Key words: HBK duck, major histocompatibility complex class I molecule, specific pathogen free, microsatellite marker