A comparative analysis of SLA-DRB1 genetic diversity in Colombian (creoles and commercial line) and worldwide swine populations

Abstract

Analysing pig class II mayor histocompatibility complex (MHC) molecules is mainly related to antigen presentation. Identifying frequently-occurring alleles in pig populations is an important aspect to be considered when developing peptide-based vaccines. Colombian creole pig populations have had to adapt to local conditions since entering Colombia; a recent census has shown low amounts of pigs which is why they are considered protected by the Colombian government. Commercial hybrids are more attractive regarding production. This research has been aimed at describing the allele distribution of Colombian pigs from diverse genetic backgrounds and comparing Colombian SLA-DRB1 locus diversity to that of internationally reported populations. Twenty SLA-DRB1 alleles were identified in the six populations analysed here using sequence-based typing. The amount of alleles ranged from six (Manta and Casco Mula) to nine (San Pedreño). Only one allele (01:02) having > 5% frequency was shared by all three commercial line populations. Allele 02:01:01 was shared by five populations (around > 5% frequency). Global FST indicated that pig populations were clearly structured, as 20.6% of total allele frequency variation was explained by differences between populations (FST = 0.206). This study’s results confirmed that the greatest diversity occurred in wild boars, thereby contrasting with low diversity in domestic pig populations.

Individual and population diversity of 20 representative olfactory receptor genes in pigs

“…Therefore, the genetic characteristics of the two protein families are similar. For swine leukocyte antigen (SLA) genes, which is the MHC genes of pig, it has been well documented that the presence of an extremely large number of alleles, a large difference in allelic constitution among different breeds, and breed-speci c alleles [42][43][44][45][46][47] are most likely to result from independent breeding histories for different breeds. In addition, the characteristics of pig OR genes analyzed in this current study showed similarities to those of the SLA genes described above.…”

Individual and population diversity of 20 representative olfactory receptor genes in pigs

“…Therefore, the genetic characteristics of the two protein families are similar. For swine leukocyte antigen ( SLA ) genes, which is the MHC genes of pig, it has been well documented that the presence of an extremely large number of alleles, a large difference in allelic constitution among different breeds, and breed-specific alleles 44 – 49 are most likely to result from independent breeding histories for different breeds. In addition, the characteristics of pig OR genes analyzed in this current study showed similarities to those of the SLA genes described above.…”

Nanovaccines against Animal Pathogens: The Latest Findings

“…The group of MHC-related genes encodes an extensive repertoire of surface proteins playing a crucial role in recognising mammalian antigens; in spite of large differences between species, their variability has been associated with susceptibility to or protection against infectious diseases and even cancer [49,50]. Most research regarding class II molecules has focused on the DRB1 locus (DRB3 in cattle) as being the most variable and having the greatest cell-related expression; on the contrary, DRA is considered practically invariant [50][51][52][53]. Manczinger et al (2019) proposed that human DRB1 MHC-II allele response could be categorised into two groups; specialists (alleles able to bind to a few epitopes) and generalists (providing protection against a broad range of pathogens).…”

“…Regarding veterinary studies, a study has explored the MHC in different species. Allele frequency and diversity in pigs has been analysed in wild and production species which are of interest, due to their biological characteristics, their use in biomedical studies, transplants, regenerative medicine, and vaccine design [53,55,56]. Hammer et al (2021), for example, used low-resolution (Lr) SLA haplotyping for characterising European SLA-I (SLA-1, SLA-2, and SLA-3) and SLA-II genes (DRB1, DQB1, DQA) in 549 pigs representing nine commercial lines from various production systems; they identified 50 class I haplotypes and 37 class II ones.…”