Polymorphism research on SLA class II genes in Canadian SPF Yorkshire and Landrace pigs / 中国实验动物学报

ABSTRACT

Objective The aim of this study was to investigate the polymorphism of SLA class II genes in Canadian SPF Yorkshire and Landrace pigs.Methods Blood samples were obtained from 15 SPF Yorkshire and 22 Landrace pigs for isolation of peripheral blood mononuclear cells respectively, and the DQB1, DRB1 and DQA genes were amplified by PCR after reverse transcription.SLA class II genes were obtained by analyzing the direct and cloning result.The polymorphism of alleles was analyzed using the DNAsp 5.0 software.Results A total of 25 alleles were identified at three genes, including eight DQB1, ten DRB1 and seven DQA, and three alleles were submitted the complete sequences for the first time.The official allele names were assigned as SLA-DQB1*0212 (KU754590), SLA-DQB1*0203 (KU754591) and DRB1*0607(KU754601) by the SLA Nomenclature Committee.Three novel DQA alleles were discovered.Five of the 15 amino acids, one of the 16 amino acids and 11 of the 19 amino acids, which bind processing antigens, showed well conserved among the alleles of DQB1, DRB1 and DQA genes in the SPF Yorkshire and Landrace pigs, respectively.Neighbor-joining tree showed that the three genes were divided into two clusters, respectively.There was a close relationship between SPF Yorkshire and Landrace pigs and foreign Yucatan miniature pigs, and it showed no obvious genetic distance with other pigs.Conclusions A total of 25 SLA class II alleles have been identified successfully in this study, and there are more abundant polymorphism for them.There is a widely distribution for SLA class II alleles identified in this study in other pig breeds.It is critical for the eventual future use of SPF Yorkshire and Landrace pigs as classical laboratory animal models.