IDENTIFYING POLYMORPHISM IN SOME GENES AND THEIR EFFECTS ON GROWTH PERFORMANCE IN HONAMLI AND HAIR GOAT BREEDS

Abstract

The aim of this study was to detect growth hormone (GH), leptin (LEP), pituitary transcription factor-1 (POU1F1), bone morphogenetic protein-15 (BMP15) and myostatin (MSTN) genes polymorphisms, to investigate the genetic structure and allele frequencies value for these polymorphisms and to determine their influence on some growth traits (live weight and linear body measurements as growth traits on 90, 120, 180 and 365 days) in Honamli and Hair goat breeds. For these purposes, a total of 300 goats were used, genotyping was performed on 150 Honamli and 150 Hair goat breeds. Genotypes were identified by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP). Phenotypic data of growth traits of each individual goat were collected. A 422 bp product and a 116 bp product of GH1 and GH2 respectively, a 450 bp product of POU1F1, a 152 bp and 400 bp product of LEP EX2 and LEP INT2 respectively, a 497 bp product of MSTN and a 141 bp product of BMP15, thus 7 loci of 5 genes, were amplified by PCR. The effect of genotypes at each locus on growth traits was assessed with general linear models. Birth weights, live weights and linear body measurements in the Honamli goat were higher in Hair goat. Investigated breeds were in Hardy-Weinberg equilibrium for GH2-HaeIII, POU1F1-Pst1 and MSTN-DraI polymorphisms, but not for the GH1-HaeIII polymorphism (p<0.001). Whereas, LEP and BMP15 genes were monomorphic in both breeds. On the other hand, no significant associations were found between examined growth traits and any of the studied polymorphisms in the Honamli and Hair goat breeds. This study reported the existence of genetic polymorphisms in the GH, POU1F1 and MSTN genes and their effects on growth traits in Honamli and Hair goat breeds were investigated for the first time. The present results led us to conclude that although the GH2- HaeIII, POU1F1-Pst1 and MSTN-DraI polymorphism presented adequate segregation for association studies in Honamli and Hair goat breeds, it does not seem to be a promising selection tool for growth traits in Honamli and Hair goat breeds.