Mc4R gene regulates feed intake, live weight, and energy balance in animals. It is one of growth and development candidate genes, as indicated by its role in energy balance and feed intake. The goal of the research was to analyze the polymorphisms of the Mc4Rxgene and their relations with growth characteristics in KaracabeyxMerino lambs. 300 Karacabey Merinoxlambs reared at the Bandırma Sheep Breeding Research Institute in Balıkesir, Turkiye, served as the research's animal subjects. The total of 1291 bp long exon and 3’UTR regions of Mc4Rigene was amplified. PCR products were analysed by DNA sequencing. A total of 6 SNP of Mc4R (g.9.T>C, g.12.G>C, g.93.G>A, g.381. G>A, g.681.G>C and g.1016. G>A) gene were identified. These SNP’s have not been inducing changes sequence of amino acids. The single nucleotide polymorphisms (SNPs) of Mc4R gene were found significant associations between muscle depth, skin thickness, back fat thickness, average daily gain and live weight. The Mc4R gene was shown to be a potential genetic marker in selection programs on sheep to improve growth traits of lambs. پرونده مقاله