MC3R基因对京海黄鸡屠体性状的遗传效应分析

Genetic effects of MC3R gene on the carcass traits in Jinghai yellow chicken

本研究以MC3R基因为鸡屠体性状的候选基因,旨在探讨其对京海黄鸡屠体性状的影响。运用PCR-SSCP方法结合测序技术,检测了MC3R基因在京海黄鸡群体中的多态性,并采用一般线性模型(GLM)分析基因型与屠体性状的遗传效应。结果显示,MC3R基因CDS序列检测区内,引物MR2、MR3和MR8扩增的片段具有多态性,其中引物MR2和MR3扩增片段均存在2个SNP位点,分别形成AA、AB、AC 3种基因型和EE、EF、FF、EH 4种基因型,引物MR8扩增片段只存在1个SNP位点,形成了KK、KL和LL 3种基因型;检测到的5个SNPs位点分别为CDS区C160A、G192T、C273T、G310A、G762A突变。关联分析结果显示,MR2位点对京海黄鸡各屠体性状(除腹脂质量)均有极显著影响(P<0.01);MR3位点各基因型(排除个体数少于3的基因型)屠体性状间差异均不显著(P<0.05),推断MR3位点对京海黄鸡屠体性状影响不显著(P>0.05);MR8位点对京海黄鸡屠体质量、胸肌质量、腿肌质量、全净膛质量、半净膛质量有极显著影响(P<0.01),对活体质量和腹脂质量有显著影响(P<0.05)。对MR2和MR8 2个位点的效应进行联合分析,结果显示,2个位点组合基因型对所有屠体性状均有显著或极显著影响(P<0.05或P<0.01),其中AB/KK基因型组合为有利基因型组合,AA/LL基因型组合为不利基因型组合。因此,本研究可为京海黄鸡分子标记辅助育种提供依据,有利于加快对京海黄鸡屠体性状选择的育种进程,同时通过本研究可推测MC3R基因对家禽的屠体性状具有很大的遗传效应,为家禽育种工作提供理论依据。

The aim of this study was to investigate the effects of MC3 R gene on carcass traits in Jinghai yellow Chicken.The PCR-SSCP approach combined with sequencing technology was applied to detect the single nucleotide polymorphisms(SNPs)of MC3 Rgene and the general linear model(GLM)was used to analyze genetic effects between different genotypes and the carcass traits of the Jinghai yellow chicken.The results showed that,in the CDS sequence zone of MC3 R gene,the fragments amplified by the primer MR2,MR3 and MR8all presented polymorphic.The fragments amplified by the primer MR2 and MR3both had 2SNPs,and formed three genotypes(AA,AB and AC)and four genotypes(EE,EF,FF and EH)respectively.And the fragment amplified by the primer MR8 had only 1SNP which formed three genotypes(KK,KL and LL).Five mutations(C160A、G192T、C273T、G310A、G762A)were detected in the CDS sequence zone.The results of the correlation analysis showed that MR2 locus had highly significant effects on all carcass traits(except abdominal fat weight)in Jinghai yellow chicken(P<0.01).The carcass traits between the genotypes of MR3locus(excluding the genotypes with less than 3individuals)were not significantly different(P>0.05),indicating that MR3 locus had no significant effects on the carcass traits in Jinghai yellow chicken(P>0.05).MR8 locus had highly significant effects on carcass weight,chest muscle weight,leg muscle weight,eviscerated weight and half eviscerated weight in Jinghai yellow chicken(P<0.01)and had significant effects on live weight and abdominal fat weight(P<0.05).The joint effects of two loci MR2 and MR8were analyzed.The results showed that,the genotype combinations of the two loci had significant effects on all carcass traits(P<0.05 or P<0.01),in which AB/KK genotype combination was a favorable genotype combination,and AA/LL genotype combination was unfavorable.Above all,this study may provide reference materials for marker-assisted breeding,and accelerate the breeding progress of the carcass traits selection in Jinghai yellow chicken.