Study On High Prolificacy Candidate Gene Inhibin Alpha Subunit Gene In Goats

To improve the goats' performance of reproduction,increase the economic benefit of breeding goats and provide foundational datum for molecular marker assistant selected breeding in high prolific goat,the PCR-SSCP and Quantitative Genetics of inhibin-α(INHA) gene were studied in Jiangsu province native goat breeds(Huanghuai goat and Yangtze River Delta White goat) and Boer goat.The method of PCR-SSCP to detect goat INHA gene single nucleotide mutations was established in this study.And the genetic variation(gene frequency,heterozygosity polymorphic information content(PIC)and effective number of alleles) of INHA gene was analyzed in three goats' breeds.Single nucleotide polymorphisms of promoter region,5 regulatory region,exon 1 of INHA gene were detected in high fecundity breeds(Huanghuai goat and Yangtze River Delta White goat) and low fecundity breed(Boer goat) by PCR-SSCP.The effect inhibin-α(INHA) gene on liter size of Huanghuai Goat was also studied.The results indicated that three genotypes were deteted in primer 2 site of 5 region of INHA gene in all three breeds, sequencing results showed two SNP mutations(260T→G and 353A missing).Huanghuai goat,Yangtze River Delta White goat and Boer goat,frequency of AA genotype was 0.8434, 0.8421 and 0.9167,frequency of AB genotype was 0.1084,0.1053 and 0.0278,and frequency of BB genotype was 0.0482,0.0526 and 0.0556,respectively.The ewes with mutation homozygous genotype BB or mutation heterozygous genotype AB had 1.25 (P＜0.01) or 0.78(P＜0.05) lambs more than those with wild type AA in Huanghuai goat, respectively.The PCR-SSCP results showed that three genotypes were also detected in primer 4 site of exon 1 of INHA gene in all three breeds,sequencing results found a mutation(C→A) at 1006 bp,and this mutation resulted in an amino acid change: Proline→Threonine.In Huanghuai goat,Yangtze River Delta White goat and Boer goat, frequency of CC genotype was 0.3214,0.4444 and 0.5526,frequency of CD genotype was 0.3929,0.4167 and 0.3421,and frequency of DD genotype was 0.2857,0.1389 and 0.1053, respectively.The ewes with mutation homozygous genotype DD or mutation heterozygous genotype CD had 0.65(P＜0.05) or 0.41(P＞0.05) lambs less than those with wild type CC in Haunghaui goat,respectively.These results preliminarily showed that the INHA gene was either a major gene that influences the prolificacy of Huanghuai goat or a molecular genetic marker in close linkage with such a gene.