Association of a non-synonymous SNP of IL17RA gene with litter size traits in Large White and Landrace pigs

Abstract

Interleukin-17 receptor A (IL17RA) is one of the cytokine receptors of the pro-inflammatory interleukin-17 (IL17) cytokine family. The IL17 and IL17RA genes are involved in inflammatory and immune responses as well as reproductive process of mammals. The purposes of this study were to examine polymorphisms in the porcine IL17RA gene and to assess its effects on litter size traits in Large White and Landrace pigs. Three non-synonymous single nucleotide polymorphisms (SNPs) in the porcine IL17RA gene were verified. The porcine IL17RA c.785C>T (p.Ala262Val) was found to be segregating in the Large White and Landrace pigs. No polymorphisms in the coding region of the porcine IL17RA gene at the two non-synonymous SNPs loci of c.997G>A (p.Val333Ile) and c.1962T>G (p.Asp654Glu) were found. The porcine IL17RA c.785C>T polymorphism was significantly associated with the total number born (TNB) and the number born alive (NBA) in Large White pigs (P<0.05). Moreover, the porcine IL17RA c.785C>T was significantly associated with the TNB, NBA, total birth weight (TBW), and total weaning weight of piglets at 21 days (TWW) in Landrace pigs (P<0.05). These results supported the importance of the porcine IL17RA gene in the litter size traits of pigs. Thus, the porcine IL17RA could be used as a potential candidate gene for improving litter size traits in pig breeding.

Association of FTH and EPOR gene polymorphisms with litter size traits in pigs

“…Association analysis of the FTH and EPOR polymorphisms was examined using the mixed model as follows: Y ijklm = µ + P i + YS j +G k +A l + e ijklm , where Y ijklm is representative of the observations of the phenotype values, μ represents the average normalized record of population, P i represents the fixed effect of the parities (i = 1 and ≥ 2), YS j represents the fixed effect of the year-seasons (j = 1-8), G k is representative of the fixed effect of the porcine FTH or EPOR genotypes (k = 1-3), or the accumulated favorable alleles for the FTH g.9537834G > A, FTH g.9537855T > C, and EPOR g.70066473C > T (k = 0-6), A l is representative of the random effect of the animal, and e ijklm represents the residual error. Besides, the additive effect was analyzed as half difference between the two homozygous genotypes and the dominance effect was calculated as the deviation of the heterozygous genotype effect from the mean effect of the two homozygous genotypes (Muñoz et al, 2007;Norseeda et al, 2021c). The least square mean values between genotype groups for each locus were compared using the least significant differences (LSD) test (P < 0.05).…”