Polymorphism of the MC4R melanocortin receptor gene in pigs of various breeds

Abstract

One of the promising candidate genes determining the level of development of productive traits of pigs is the melanocortin - 4 receptor gene (MC4R). MC4R is a classic a-melanocytic hormone receptor (a-MCH) and takes a direct part in the metabolism of adipose tissue. In some swine populations, the single-nucleotide polymorphism of this gene is significantly associated with feed and meat qualities, in particular, with the thickness of spinal fat. The paper presents the results of a study of the gene polymorphism of melanocortin-MC4R receptor in purebred pigs of two breeds-Landras and Yorkshire of Danish selection. A significantly different polymorphism in this gene between the two rocks was revealed. In pigs of the Landras breed allele a prevails in the form of homozygous AA, in pigs of the Yorkshire breed allele a also prevails, but in the heterozygous state (AG). As for the other G allele, the frequency of Landrace minor (0,185) and this allele is found mostly in the form of heterozygotes AG (37,23 %). Pigs of the Yorkshire breed, the G allele, which is associated with lower thickness of subcutaneous fat, occurs much more frequently than in Landrace (0,395 against 0,185). The number of homozygous GG at Yorkshire much higher than that of Landrace (16,6 % vs 2,12 %). It is concluded that the higher frequency of allele of the MC4R gene in the Yorkshire hog population, compared to landrass animals, is connected, apparently, with heterogeneous origin of Yorkshire hogs or indicates a weak involvement of polymorphism of the MC4R gene in artificial selection.