Determining promaternal breeds in the final hybrids of pigs using mitochondrial genome polymorphism

The purpose of this work was to determine the origin of pigs of the final hybrid (Large White×Landrace)×Maxgro using mitochondrial DNA markers. Bristle from the auricle of pigs (Large White×Landrace)×Maxgro was used as genetic material. DNA isolation was carried out according to the method of S. M. Korinnyi et al. 2005, using the Chelex - 100 ion exchange resin. The method of PCR-amplified restriction fragment length polymorphism (PCR-RFLP) was used to analyze the mitochondrial genome. Sections of the D-loop of the pig mitochondrial genome with a size of 428 nucleotide pairs (with Tas 1 recognition sites at positions 15558, 15580, 15616, 15714, 15758) are subject to analysis. The comparison of maternally inherited restriction fragments in the breed made it possible to obtain reliable information about the origin of the experimentally studied sample of pigs of the final hybrid (n=15) from LLC "Globynsky Svynocompleks", Globyno, Poltava Region, Ukraine.The laboratory research was carried out on the basis of the Institute of Pig Breeding and AIP of the National Academy of Agrarian Sciences of Ukraine in the laboratory of genetics. By analyzing nucleotide sequences, one monomorphic site at position 15558 bp and three polymorphic sites at positions 15580, 15616, and 15758 were identified and experimentally studied for endonuclease Tas I (↓AATT). To systematize the combinations of restriction fragments of mitochondrial DNA, three breed-specific mitochondrial haplotypes were determined in the experimentally studied sample of hybrid pigs (n=15). As a result it was obtained the haplotypes of the studied pig population (Large White×Landrace)×Maxgro according to mitochondrial DNA markers: 4 animals with haplotype C - Landrace, Hampshire, Wales,a subspecies of wild pig (Ukraine, Poland); 5 pigs have mitochondrial haplotype N –the Large White (Asian type), Berkshire, the Asian wild boar; 6 pigs with mitochondrial haplotype O are Landraces, a subspecies of wild boar (Scandinavia). The obtained results indicate that two-breed sows were the result of direct the (Large White×Landrace) and reciprocal crossing (Landrace×Large White). Based on the example of the developed systematization of the combination of restriction fragments by Pocherniaev K. F., in the future it is proposed to create a database of reference haplotypes of mitochondrial DNA of pigs of the final hybrid (Large White×Landrace)×Maxgro. It will be used in future studies to reconstruct the demographic history of commercial breeds of hybrid pigs of foreign selection. The work was carried out with the support of the National Academy of Agrarian Sciences of Ukraine 31.01.00.07.F. "To investigate the pleiotropic effect of genes whose SNPs are used in marker-associated selection of pigs." SR No. 0121U109838. Key words: mitochondrial DNA, D-loop, pigs, final hybrid, (Large White×Landrace)×Maxgro, haplotype, haplogroup, PCR-PDRF, selection, origin.