Polymorphisms in BMP-2 gene and their associations with growth traits in goats

BMPs plays an important role in skeletal development. In this study, PCR-SSCP and DNA sequencing methods were employed to screen the genetic variation of caprine BMP-2 gene in 299 goats from three breeds (Boer goat, Chinese Xuhuai white goat and Chinese Haimen goat). Three fragments of BMP-2 gene were investigated, only 3' flanking region of BMP-2 gene showed polymorphism. The alignment between nucleotide sequences of AY714781.1 in GenBank and the sequencing results of three PCR products with different patterns revealed that there was one mutation (AY714781.1: g.A172G) in 3' flanking region of BMP-2 gene, which constructed three genotypes (AA, AB, BB). The frequencies of allele A and genotype AA were dominant in all three breeds. Frequency of allele B in Haimen goat breed was significantly lower than that of the other two breeds. The genotype distributions were in good agreement with Hardy-Weinberg equilibrium (P greater than 0.05) in each breed. The PIC (Polymorphism Information Content) values in three populations were 0.3261, 0.2558, 0.1663 for Boer goat, Xuhuai White goat and Haimen goat respectively. It was indicated that individuals of Boer goats with genotype BB were significantly higher than those of individuals with genotype AA in body trunk index (P less than 0.01). No polymorphism was detected in the exon3.