Abstract: The bone morphogenetic protein 2 (BMP2) gene was studied as a candidate gene for high prolificacy in some goat breeds (Capra hircus). Single nucleotide polymorphisms (SNPs) of two exons (exons 2 and 3) of BMP2 gene were detected in high prolificacy breed (Jining Grey goat), moderate prolificacy breed (Boer goat) and low prolificacy breeds (Inner Mongolia Cashmere and Angora goats) by polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP). No polymorphism was detected in the amplified region in the four goat breeds tested. DNA fragments of exons 2 and 3 of Jining Grey goat BMP2 gene were cloned into pSRUE-T vector. The positive clones were further identified by PCR. The nucleotide sequences were detected and the amino acid sequences of these fragments were deduced. The comparison of the fragments of two exons of Jining Grey goat BMP2 gene with those of human, chimpanzee, cattle, dog, rat and mouse BMP2 gene showed that the homologies of the nucleotide sequences and amino acid sequences of the fragments among these seven species were from 86.5% to 91.3% and from 88.8% to 99% respectively. Three special variations were found in the 131st, 353rd, 365th position of amino acid sequence, which was threonine, aspartic acid, proline in Jining Grey goats and proline, valine, leucine in other species respectively. The results indicated that the exons 2 and 3 of BMP2 gene were highly conserved among mammals, and may not be the functional domains that affect the high prolificacy in goats.

Key words: goat; bone morphogenetic protein 2 gene; PCR-SSCP