Polymorphism Identification in the Coding Sequences (ORFs) of the Porcine Pregnancy-Associated Glycoprotein 2-like Gene Subfamily in Pigs

Pregnancy-associated glycoproteins (PAGs) are a polygenic family with many scattered genes and pseudogenes resulting from the duplication or fusion of a pseudogene with expression beginning in the trophoblast during the peri-implantation period and continuing in the trophectoderm. In this study, single-nucleotide polymorphism (SNP) and insertion/deletion (InDels) in the open reading frame (nine exons) of crossbreed pigs are reported for the first time. Novel SNPs/InDels were researched using genomic DNA templates isolated from the leukocytes of crossbreed pigs (N = 25), which were amplified, gel-out-purified, and sequenced. Sixteen SNPs and one InDel (g.6961_6966 Ins TGCCAA) were identified in the crossbreed pigs. In silico analysis revealed that among 16 SNPs, only 10 SNPs cause amino acid (aa) substitutions, and InDel codes asparagine (N²⁹⁸) and alanine (A²⁹⁹). The results provide a novel broad-based database (main pattern) that will be critical for future research into the possible correlations between the SNP genotypes of the <i>pPAG2-L</i> subfamily in pigs of various breeds whose reproductive traits are known.