Differential Expression Of Agouti MRNA And Express Affection Of5’UTR Variation In Different Goat Coat Color

Research the Agouti gene which control goat coat colors has positive theoretical andpractical significance to reveal the formation mechanism of goat fur and innovative use ofcolor genes in fur animal breeding. The real-time quantitative PCR was used to investigatethe expression level of Agouti mRNA in goat skin with white, gray with brown and blackcoat color in order to explore its differential expression and provide useful information forstudy of coat color formation mechanism. The experiment compared with white goat, use2-△△CTto calculate Agouti gene’s Rel Quant in white, gray with brown and black skin, theresule was white> black> gray with brown. There were significant difference of AgoutimRNA expression between black and gray with brown, between white and gray with brownbut no significant difference between white and black. Result shew that the Agouti genemRNA expression quantity in goat skin tissue of different color was different.After analysing5’UTR region of goat Agouti gene, three point mutations were found,which were g.C6474T，g.C6579T and g.T6703A. Get nine genotypes, they were GG、AA、GA; GG、AA、GA; AA、TT、AT respectively. The three point mutations were related to goatcolor phenotype. On three sites, white goat’s heterozygote genotype frequency wassignificantly greater than the homozygote, brown with grey goat heterozygote genotypefrequency was significantly greater than homozygote too. The black goat was homozygotegenotype frequency bigger than the heterozygote. The allele frequency of different mutationsexisted significant differences in the black and white goat. It indicated that mutation has animpact on the color, and concluded that mutations also influence the Agouti gene mRNAexpression.Analyse and compare the Agouti gene mRNA expression quantity in different genotypeof each SNP, we found that there weresn’t significant differences between differentgenotypes. The interaction result of colour with genotype shew that, in black goatpopulation，the expression quantity was greater than in white on g.C6579T site, theexpression quantity of homozygote was greater than heterozygote in black and brown withgrey goat populations, but there was no significant difference in white goat population.thelocus mutation has influence to Agouti gene mRNA expression quantity of different colors.The significance test results of different genotypes expression quantity shew that, thesignificant difference were between CC and CT on g.C6579T, and between AT and TT on g.T6703A. The others expression difference was not significant between genotypes. We cansay that5’UTR variation has influence to mRNA expression quantity in Agouti gene ofdifferent goat coat color.