An investigation of genes that would be associated with udder conformation characteristics in karacabey merino sheep by genome wide association analysis (GWAS)

The aim of study was identify genes affecting udder conformation traits in Karacabey Merino sheep. Phenotypic data of 10 udder traits were collected from a population of 228 Karacabey Merino sheep, and genotyping was performed on all animals by this aim. After conducting genome-wide association studies (GWAS) on the obtained data, a total of 33 SNP regions were identified: 24 SNPs associated with udder conformation traits on a genome-wide association and 9 SNPs associated with chromosomal-wide association. It was observed that 29 of the identified 33 SNPs are located within or near 500 KB of 29 different genes and are associated with 10 different udder conformation traits. Among the genes related to udder conformation traits, ROR1, COLEC12, GRID1 were identified for teat length; KCNN2, RBMS3, ENSOARG00020013095, TMEM241 for teat width; SDR16C5 for distance between teats; HSF2BP, DIRAS2, SLC26A4, ENSOARG00020012980 for teat placement; TFEC, SLC2525A13 for udder depth; UBXN10, TMEM182, USP46, CACNA2D3, ENSOARG00020034008 for udder quarter separation; ENSOARG00020035000, SMAD3, GRHL2 for teat type; ADRA1A, SLC25A21 for udder shape; and MRPL3, MTHFD1L, ANKH, SRRM4, and SLC25A21 for udder attachment. The results of this study was indicated that the using of microarray SNP chip technology in early-stage breeding selection based on udder traits in Karacabey Merino ewes is importand for identifying potentially influential SNPs for udder conformation, and determination of possibilities for their use in genomic selection.