The COXII Haplotypes and their Association with Productive Traits in Large White Breed Pigs

The mitochondrial genome encodes key electron transfer chain (ETC) proteins which produce the vast majority of cellular ATP. Sequence analysis of maternal inherited mitochondrial DNA is an effective way to assess the individual characteristics of commercial breeding lines of pigs. The aims of our study were to analyze the nucleotide sequence of the mitochondrial gene COXII in Large White pigs, to search for polymorphisms and to evaluate their associations with pigs productive abilities and the backfat thickness. The studied pigs of Large White were divided in two groups. The first group (LW-1) was consisted of pigs bred in Russian Federation since 1998. The second group (LW-2) included pigs of Large White imported in 2014 to Russia from England. To evaluate the associations of the COXII gene haplotypes with productive qualities, 96 sow LW-1 were selected. The variability analysis of the COXII revealed the presence of three haplotypes: Hap_1 (TTTCTGGAT, in positions m.8292, m.8334, m.8419, m.8466, m.8526, m.8634, m.8664, m.8682, m.8682, m.8694 respectively), Hap_2 (CCCCCAAGC) and Hap_3 (TTTTTGGAT). We have obtained the results on the association of the COXII polymorphic variants in the loci (m.C8292, m.C8334, m.C8419, m.C8526, m.A8634, m.A8664, m.G8682, m.C8694) that are typical for Hap_2, with higher value of backfat thickness in pigs.