兔黑素皮质素受体4(MC4R)基因多态性及其与体重及屠体性状的关联研究

以哈尔滨白兔、天府黑兔、比利时兔、齐卡巨型兔以及加利福尼亚兔5个肉兔品种共220个个体为研究对象, 采用PCR-SSCP技术和克隆测序技术进行SNPs检测和基因型的分析。结果发现兔MC4R基因237位发生转换突变(A→G), 5个品种内的AA基因型和A等位基因频率均分别高于AG基因型和G等位基因, 而哈尔滨白兔、比利时兔以及齐卡巨型兔3个品种兔的AG基因型频率和G等位基因频率明显高于天府黑兔和加利福尼亚兔。单位点基因型与屠体性状、饲料转化率以及熟肉率的最小二乘分析表明; AG基因型与兔的体重、全净膛重以及饲料转化率有显著的关系(P<0.05), 而与熟肉率的关系不显著(P>0.05)。结果表明, MC4R基因可以作为影响和控制兔体重及屠体性状的候选基因。

Association between single nucleotide polymorphism of MC4R gene and carcass traits in rabbits

Single nucleotide polymorphisms in the coding sequence of melanoeortin-4 receptor (MC4R) gene were detected by PCR-SSCP and DNA sequencing method in Harbin white rabbit, Tianfu black rabbit, Belgian hare, ZIKA rabbit, and California rabbit breeds. A→G conversion mutation at base position 237 was found with high frequency in Harbin white rabbit, Belgian hare, and Zika rabbit and low frequency in Tianfu black rabbit and California rabbit. The allele A was pre-dominant allele for each of meat rabbit breeds. AA genotype frequency was higher than AG genotype in the five studied rabbit breeds. GLM analysis for the effect of genotypes on performance traits demonstrated that AG genotype was signifi-cantly associated with body weight, eviscerated weight and feed conversion efficiency (P<0.05), but not significantly asso-ciated with cooking loss (P>0.05). It was concluded from the results that MC4R gene could be a candidate modifier gene that affects or controls body weight and carcass traits of rabbit.