Research Of Candidate Genes Related To Prolific Character On Liaoning Cashmere Goats

Using the method of"random sampling in typical colonies of the central area of the habitat",62 Liaoning cashmere Goats in Liaoyang ,Liaoning Province, studying the prolificacy gene of Liaoning cashmere goats and investigating the related genes which influencing the production performance of Liaoning cashmere goats by molecular genetic markers method and then establish the reasonable selection fundament of Liaoning cashmere goats. This study choose the second parity ewes of Liaoning cashmere goats as experimental material, extract the genomic DNA by extracting the blood in the jugular vein blood and check the samples of sheep lambing records.Polymorphisms of INHA (Inhibin-a subunit gene) and RARG(retinoic acid receptor gamma) were studied as candidate genes in Liaoning cashmere goat and analyzed for their mutations and genetic effects. PCR-RFLP were used to detect the SNP( single nucleotide polymorphism)of these gene in this study. Then sequencing, sequence analysis, ascertaining mutation type and association analysis between yean trait and polymorphism site.The main results were showing as follows:1. Polymorphism of INHA was studied in Liaoning cashmere goat. A new mutation T-446C(Accession number:EF602161) was discovered at the promoter in the goat. Naeâ… polymorphism was detected at this site. Different genotypes were determined in Liaoning cashmere goat by restriction fragment length polymorphism (RFLP). The value of polymorphism information content indicated that this was a moderate polymorphism in Liaoning cashmere goat. Theχ2 test indicated that the polymorphic locus in Liaoning cashmere goat did not fit Hardy-Weinberg equilibrium (P<0.05). Theχ2 test of associational analysis between genotypic distribution and twinning or monotocous trait in Liaoning cashmere goat showed that the difference was significant (P<0.05).2. Compared the sequence of human mRNA (Accession number: AJ250835) and bovine DNA sequence (Accession number: NM₀011307560), designed primers, amplified the RARG exon 3 region of goat successfully,and carried out the sequencing;3. Homology of exon 3 sequence of RARG gene between Liaoning cashmere goat and cattle was 99.4 %, but compared with human ,the homology of exon 3 sequence of RARG gene of Liaoning cashmere goat was 92.5 %;this indicated to have higher conservative inheritance of the exon sequence on RARG gene between goat and cattle;4. RARG gene was not detected mutable site at exon 3 in Liaoning cashmere goat and its homology was 100%.