AGRICULTURAL BIOLOGY, 2016, V. 51, ¹ 2, pp. 182-193 Genomic breeding doi: 10.15389/agrobiology.2016.2.182rus doi: 10.15389/agrobiology.2016.2.182eng GENOME-WIDE ASSOCIATION STUDY FOR MILK PRODUCTION AND REPRODUCTION TRAITS IN RUSSIAN HOLSTEIN CATTLE POPULATION A.A. SERMYAGIN1, E.A. GLADYR’1, S.N. KHARITONOV1, A.N. ERMILOV1, N.I. STREKOZOV1, G. BREM1, 2, N.A. ZINOVIEVA1 Dubrovitsy, Podolsk Region, Moscow Province, 142132 Russia, e-mail alex_sermyagin85@mail.ru Federal Agency of Scientific Organizations, pos. <...> Abstract Genome-wide association study (GWAS) has been proven as a powerful tool for identifying genomic variants associated with economically important traits in domestic animal species. <...> The objective of our study was to evaluate the wholegenome associations between single nucleotide polymorphisms (SNPs) and estimated breeding values (EBVs) for milk production and reproduction traits in Russian Holsteins. <...> SNPs screening was performed in 195 progeny-tested and 61 young bulls using Illumina Bovine SNP50 v2 BeadChip. <...> EBVs were calculated for milk production traits (305-d milk yield (MY), milk fat content (FC), milk protein content (PC), milk fat yield (FY) and milk protein yield (PY)) and reproduction performances (age at fist calving (CA), calving difficulty (CD), conception rate (CR), days open (DO), gestation length (GL) and interval between calving (CI)) using BLUP Sire Model approach. <...> In total, 41370 SNPs were selected for the association analysis based on the quality control results. <...> Direct genomic values (DGV) were calculated by GBLUP approach using genomic relationship matrix (G). <...> Genomic EBVs (GEBVs) were calculated as combination of residual polygenic effects (EBV) with the DGV. <...> To increase the probabilities of GWAS values we used the GEBV values for young bulls, whereas deregressed DGV values were used for progeny-tested bulls. <...> The Bonferroni correction test for detection of significant associations and local false discovery rate (LocFdr) were used to check a type I errors in null-cases hypothesis. <...> Heritability coefficient values for reproduction traits ranged from 0.035 for CR to 0.221 CA, whereas for milk production traits they were <...>