Insertion of 275-bp SINE into first intron of PDIA4 gene is associated with litter size in Xiang pigs

Abstract The aim of the study was to investigate the SINE polymorphism in Xiang, Kele, Qianbei black, Jiangkouluobo, Large White, and Duroc pig breeds. The PCR based detection method was conducted to identify the short interspersed nuclear element (SINE) polymorphism in the PDIA 4 gene. There were greater frequencies of the SINE−/− genotypes in Xiang pigs (55.9%) as compared with other pig breed groups. There was an association between this 275 bp SINE polymorphism and litter size ( P  = 0.003). The homozygous SINE+/+ genotype of the PDIA 4 gene had a 1.45-piglets larger litter sizes compared to those with the homozygous SINE−/− genotype. Furthermore, there were assessments of mRNA and protein abundances as a result of PDIA 4 gene expression in the ovaries of Xiang pigs for the three different SINE genotypes, and the results indicated that relative abundances of PDIA 4 mRNA and protein was greater for the SINE−/− and SINE−/+ genotypes compared with the SINE+/+ genotype ( P  PDIA 4 gene and could be used as a candidate DNA marker for the selection for litter size in Xiang pigs.