Genetic variation in decorative chicken breeds based on single nucleotide substitutions in the LCORL gene

Relevance . Single nucleotide polymorphisms (SNPs) are important markers of genetic variation in chickens that occur in the genome with high frequency. The identification and characterization of such markers allow characterization of breeds in terms of their genetic traits. The aim of this work was to evaluate polymorphism in the LCORL gene in ornamental chicken breeds based on single nucleotide polymorphisms. Methods . Groups of ornamental chicken breeds: Novopavlovskaya golden (n = 48), silk (n = 30), dwarf cochinchin (n = 30) were formed for the research. The LCORL gene region was analyzed by three single nucleotide polymorphisms (rs14491003, 236 G/T and 503A/G) using the PCR-PDRF method. Results .The rs14491003 polymorphism was detected only in the population of Novopavlovskaya golden hens, where 83.3% of individuals had the CC genotype. For SNP 236G/T only in the sample of silk breed hens three possible variants of genotypes were detected, and the frequency of G and T allele was 46.7% and 53.3% respectively. Three genotypes of the LCORL gene were identified by SNP 503A/G in all poultry samples. For silk breed chickens, high frequency was found for allele A (71.7%), and for Novopavlovsk golden and dwarf cochinchin breeds — allele G (69.8% and 60.0%, respectively). When analyzing allele frequencies for all polymorphic SNPs, no shift in genetic equilibrium was detected (χ2 ˂ 3.84). The obtained results indicate that chickens of ornamental breeds have breed peculiarities caused by polymorphic variants of the LCORL gene, which confirms the functional role of this gene in the processes of formation and growth of skeletal bones in chickens of different breeding directions.