Polimorfismo genético da leptina e do receptor do hormônio do crescimento em caprinos

Abstract

This study aimed to avaluate the relationship the polymorphism from the leptin gene (LEP), specifically exon 2, and from the microsatellite of the growth hormone receptor (GHRSSR) with the weight and weaning characteristics of animal breeds Anglo-Nubian, and Boer, to identify useful markers for selecting goats of high genetic merit. It was obtained the allele frequencies and heterozygosity with the Toolkit (PARK, 2001). The test for the Hardy-Weinberg equilibrium was performed with GenePop program according to Rousset (2008), and showed that the markers were in desequilibrium in populations. Observed heterozygosity values for LEP were greater than expected and all animals showed the same electrophoretic pattern with two alleles (150 and 152 bp). It was detected with GHR locus five alleles ranging from 90 to 125 bp examined in populations. The genotypes influence of polymorphic fragments of GHR and leptin on animals development was evaluated using the birth weight (BW) and weaning (PD), by analysis of variance and mean test with the GLM procedure of (SAS, 1999). The genotypes showed a significant effect on birth weight (BW) and weaning (PD). It is necessary to study of these polymorphisms on a larger sample of animals to confirm the effect on growth characteristics.