Pırlak Koyun Irkında Bir Batında Doğan Yavru Sayısı ile Ilişkili PRL ve BHR Genlerindeki inDel Varyasyonlar

Abstract

Numerous molecular genotyping methods are available to analyse local livestock populations at molecular level in which traditional Polymerase Chain Reaction (PCR) guided by specific oligonucleotides is a fast and cost-effective method to investigate single genes. Until today, many genes which are of major effects on litter size have been reported in sheep. Genetic variations in these genes shaping the expression profile at DNA level may lead to differences in litter size among the sheep breeds. This is the first attempt to investigate insertion/deletion (inDel) variations in Prolactin (PRL) intron 2 and Growth Hormone Receptor (GHR) intron 3 and intron 4 genes in Pirlak sheep breed via traditional PCR technique. A total of 100 unrelated animals sampled from representative herds reared in Antalya were genotyped based on absence/presence of 23 base pairs (bp) length inDel in which three genotypes (II, ID, and DD) were detected in all loci. I and D allele frequency were 0.421 and 0.579, respectively in terms of PRL-intron 2 locus. I / D allele frequencies were found as 0.599 / 0.401 and 0.372 / 0.628 in GHR intron 3 and intron 4, respectively. The lowest II (0.181) and DD (0.177) genotype frequencies were detected in GHR-intron 4 and GHR-intron 3 loci, respectively. The lowest (0.177 for DD) and highest (0.448 for ID) genotype frequencies were detected in GHR intron 3 locus across the population. Significant deviation from Hardy-Weinberg Equilibrium (HWE) was detected only in PRL-intron 2 locus. The results of the present study confirm that Pirlak breed conserves sufficient genetic variation in PRL and GHR gene regions which could be utilized in selection strategies in order to increase litter size in the future.