Association between Genotypes of the Isocitrate Dehydrogenase 3, beta subunit (IDH3B) Gene and Carcass Traits in an F₂Crossbred Population of Landrace × Jeju (Korea) Black Pigs

Abstract

This study tested the association between genetic polymorphisms of the isocitrate dehydrogenase 3, beta subunit (IDH3B) gene and economic traits in an F2 crossbred population of Landrace × Jeju (South Korea) Black pigs. A 304-bp insertion/deletion mutation in promoter region was screened for determining genotypes of the IDH3B gene in a total of 1,105 F2 pigs. Three genotypes (AA, AB, and BB) were identified in the founder, F1, and F2 populations. Association analysis showed significant differences in carcass weights (CW), backfat thicknesses in three positions of the body (4 th -5 th ribs, BF5; 11 th -12 th ribs, BF12; 13 th rib-1 st lumbar, BFL), and carcass lengths (CL) (p<0.05), but not in meat color (MC), eye muscle area (EMA), or marbling scores (MARB) (p>0.05). The F2 IDH3B BB homozygotes showed heavier CW (80.790±0.725 kg) and shorter CL (101.875±0.336 cm) than the other genotypes (p<0.05). In addition, the BF levels between the 4 th -5 th and 11 th -12 th vertebrae were thicker in the carcasses of pigs with the IDH3B BB genotype than with the other genotypes (p<0.05). These results suggested that genetic variations in the IDH3B gene may serve as molecular genetic markers for improving the Landrace × Jeju Black pig crossbreeding systems.