The Relationship of the Genotype of the LEPR Gene with a Number of Carcass Traits of Sheep

Abstract

This study was conducted in Suq Al-Shuyoukh district, south of Thi-Qar Governorate, on local sheep group, included the slaughter of a sample of sheep consisting of 48 animals. The live body weight, the age and sex of the animal were recorded, and a blood sample was taken for each animal, and some carcass traits have been recorded. Blood samples were used for the purpose of DNA extraction (Molecular screening of the target segment of the leptin receptor gene, with the aim of determining the genotypes of the leptin receptor gene, by Polymerase Chain Reaction (PCR) technology, and the relationship genotypes to a number of carcass traits of local sheep). The results of the PCR analysis of the leptin receptor gene (LEPR) of local sheep, showed the presence of a single mutation at position 227 within the studied region of the leptin receptor gene, appeared with three genotypes: AA, AG, and GG, in which the nitrogenous base A changed to G, the mutation occurred in the region of intron number 8. No change or mutation occurred in exon 8, as for the location of the mutation on chromosome No. 20, it occurred at site 41221676, therefore, this mutation is considered a silent mutation, it produced three genotypes: AG, AA, and GG, and their distribution rates were 62, 21, and 17%, respectively. The difference between these percentages was highly significant, by calculating the allelic frequency, the A allele was superior (0.52) over the G allele (0.48) of the leptin receptor gene in the studied sheep sample. The results of the current study showed highly significant differences (P<0.01) between the three genotypes of the target gene segment of the leptin receptor gene LEPR for most of the studied traits.