Identification of IGFBP-2 Gene Polymorphism and Its Association with Performance Traits in Large White Yorkshire Pigs

Piggery promises distinct qualities like early maturity, high fecundity, produces up to 8–12 piglets in each farrowing, high feed conversion efficiency etc. that make it low-cost profitable enterprise. The objective of this study was to evaluate the genetic diversity in Large White Yorkshire pigs based on variations in IGFBP-2 gene. A total of 100 blood samples were collected from the pigs and polymorphism was explored in IGFBP-2 gene using PCR-RFLP technique. A 245 bp fragment in intron 2 of IGFBP-2 gene was amplified using PCR. Amplified PCR products of IGFBP-2 gene was digested using MspI restriction enzymes. In this study, polymorphic patterns were revealed for the IGFBP-2 gene. Two types of genotypes i.e. CC (55 and 190 bp) and CT (55, 190 and 245 bp) were observed for the targeted loci of intron 2 of IGFBP-2 gene. CC genotype was found to be dominant with frequency as 0.88. Frequencies of ‘C’ and ‘T’ alleles were 0.94 and 0.06 in Large White Yorkshire pigs. Results of Chi-squares test showed that the targeted locus of IGFBP-2 gene was in Hardy-Weinberg equilibrium (p < 0.05) in screened pig population. The CT genotyped animals had significantly higher litter size at birth (8.83 ± 0.46) and litter weight at birth (9.98 ± 0.42 kg) as compared to homozygous CC genotyped pigs. A total of 13 samples of intron 2 region of IGFBP-2 gene were sequenced and on comparison of sequencing results with reference sequence of Duroc cross (BV727778), one SNP was found at g. 278T > C locus and there was change in nucleotide at one position i.e. g. 171 A > G (Transition). In conclusion, favored genotypes of the IGFBP-2 gene may be propagated further in Large White Yorkshire pigs through breeding programmes. There is need to explore the association of identified SNPs with production and reproduction traits in large sample size of Large White Yorkshire pigs.