Investigation of G1 (c.260G>A) polymorphism in exon 1 of GDF9 gene in Turkish sheep breed Karayaka

Abstract

Abstract: GDF9 is an essential gene for normal follicular development and prolificacy in sheep. The aim of this study was to determine the genetic polymorphism and G1 mutation of GDF9 gene exon 1 in 100 Karayaka ewes, belonging to four subpopulations in the Black Sea Region provinces of Turkey. Based on DNA sequence results, two alleles (A and G) and two genotypes (GG and GA) were determined with the restriction fragment length polymorphism analysis of PCR-amplified fragments (PCR-RFLP) method. The frequencies of mutant (A) and wild-type (G) alleles were detected as 0.10 and 0.90. The frequencies of GG and GA genotypes were calculated as 0.79 and 0.21, respectively. Twenty-one percent of the studied animals were heterozygous GA genotype. The values for observed (Ho) and expected (He) heterozygosity for GDF9-exon 1 were estimated as 0.210 and 0.189, respectively. DNA sequence results revealed that Karayaka breed had the mutation G1 (c.260G>A). In conclusion, this mutation might be used as a potential marker to improve litter size rate in Karayaka sheep as evidenced in other sheep breeds. Key words: Karayaka sheep, litter size, GDF9 gene exon 1, PCR-RFLP analysis, Hhal restriction enzyme