Objective: To study the polymorphism of SLA class II gene in SPF large white and landrace pigs.
Methods: 15 SPF large white pigs and 22 landrace pigs were collected for anticoagulation, peripheral blood lymphocytes were isolated, total RNA was extracted, and DQB1, DRB1 and DQA genes were amplified and sequenced by RT-PCR after reverse transcription. SLA class II allelic sequence polymorphism.
Results: A total of 25 alleles were obtained for 3 genes, including 8 DQB1, 10 DRB1 and 7 DQA, all of which were officially named by the ISAG SLA Nomenclature Committee, and 3 alleles were named DQB1 by submitting complete sequences for the first time. *02:12 (KU754590), DQB1*02:03 (KU754591) and DRB1*06:07 (KU754601), 3 DQA alleles were newly discovered alleles. Among the 15 amino acids of DQB1 alleles in SPF large white pigs and landrace pigs that bind to exogenous antigens, a total of 5 amino acids are highly conserved; among the 16 exogenous antigen recognition sites of DRB1 alleles, only 1 The site is highly conserved; 11 of the 19 antigen-binding sites of the DQA allele are highly conserved. The molecular phylogenetic tree of amino acid sequences of SLA class II genes showed that the three genes were clustered into two categories, which were closely related to foreign Yucatan miniature pigs, but had no obvious genetic distance from other pig breeds.
Conclusion: Twenty-five SLA class II alleles in Large White and Landrace pigs were successfully identified and found to have relatively abundant polymorphisms. The obtained SLA class II alleles were also widely distributed in other breeds of pigs with diversity. The results of this study have an important role in the development of large white pigs and landrace pigs into classic experimental animal models.