Polymorphism in exon 2 of INHBB gene and its relationship with litter size in Jining Grey goats.

摘要

The inhibin beta _B (INHBB) gene was studied as a candidate gene for the prolificacy of Jining Grey goats. According to the sequence of bovine INHBB gene, two pairs of primers were designed to detect single nucleotide polymorphism in exon 2 of INHBB gene in high-prolificacy (Jining Grey) and low-prolificacy (Inner Mongolia Cashmere and Angora) goats by polymerase chain reaction-single strand conformation polymorphism method. Only the amplified products of primer P2 showed polymorphism. Three genotypes (AA, AB and BB) were identified in Jining Grey and two (AB and BB) in Inner Mongolia Cashmere and Angora goats. Sequencing revealed one single nucleotide mutation (A->G) at base 782 of exon 2 of INHBB gene in BB genotype compared to genotype AA. In Jining Grey goats the frequencies of A and B alleles were 0.318 and 0.682 while of AA, AB and BB genotypes reached 0.068, 0.500 and 0.432, respectively. The Jining Grey goats remained in Hardy-Weinberg equilibrium (chi-square=3.36, P=0.1861). These of genotype AA delivered by 0.73 (P<0.05) or 0.84 (P<0.05) kids more than those with genotype AB or BB, while does of genotype AB - by 0.11 (P>0.05) kids more than did does of genotype BB.