As a result of the realized in the conditions of the Republic of Belarus research on revealing the influence of polymorphism character and the influence of presence of various allelomorphic variants of IGF-2 gene in breeding boars genotype on fattening and carcass traits of stores of Belarusian large white and Belarusian meat breeds it was established: 1. frequency of occurrence of desired QQ genotype among boars of the Belarusian meat breed was rather low and has made 10%. Among boars of the Belarus large white breed the given genotype has not been revealed. Heterozygotic genotype Qq had a rather wide range - from 26,6% at boars of the Belarusian meat breed to 43,2% at boars of the Belarusian large white breed; 2. fattening boars of both studied breeds which had been received from the boars bearing in their genome Qq genotypes of IGF-2gene showed the tendency for predominance in fattening and carcass traits over their herdmates which had been received from the boars bearing in their genome qq genotypes; 3. The posterity of boars of the Belarusian meat breed bearing in their genome the homozygous QQ genotype, authentically surpassed in fattening and carcass traits their analogues which had been obtained from fathers with a genotype qq. The following traits were higher: age of achievement of body weight; daily average weight gain in case of fattening; feed expenses per unit of live weight gain; slaughter yield; weight of a back third of half carcass. Research results showed, that IGF2gene (a gene of the insulin-like growth factor) could be a perspective candidate gene which makes it possible to predict the growing capacity and carcass trait of pigs of Belarusian breeds. Taking into consideration the influence undesired q allele, for the increasing of fattening and carcass traits of pigs it was possible to recommend the realization of estimation of replacement boar pigs using the data analysis of their genotype of IGF2 gene, as additional criterion of their selection