Laboratory of Animal Breeding and Genetics, Graduate School of Agriculture, Kyoto University, Kitashirakawa, Sakyoku, Kyoto, Japan.
Anim Sci J. 2009 Dec;80(6):631-5. doi: 10.1111/j.1740-0929.2009.00688.x.
Marbling, defined by the amount and distribution of intramuscular fat, is an economically important trait of beef cattle in Japan. The c2-11#2 expressed sequence tag (EST) has been previously shown to possess expression difference in musculus longissimus muscle between low-marbled and high-marbled steer groups, and to be located within genomic region of a quantitative trait locus for marbling. Thus, the ribosomal protein L27a (RPL27A) gene containing the c2-11#2 EST sequence was considered as a positional candidate for the gene responsible for marbling. In the present study, a single nucleotide polymorphism (SNP) in the promoter region of the RPL27A, referred to as g.3109537C>T, was detected between the 2 steer groups. The SNP was associated with the predicted breeding value for beef marbling standard number by the analyses using Japanese Black beef cattle population. The effect of genotypes of the SNP on the predicted breeding value for subcutaneous fat thickness was not statistically significant. These findings suggest that the RPL27A SNP may be useful for effective marker-assisted selection to increase the levels of marbling in Japanese Black beef cattle.
大理石花纹是指肌肉内脂肪的含量和分布，是日本肉牛的一个重要经济性状。先前的研究表明，c2-11#2 表达序列标签（EST）在低大理石花纹和高大理石花纹牛群的背最长肌中存在表达差异，并且位于大理石花纹数量性状基因座的基因组区域内。因此，含有 c2-11#2 EST 序列的核糖体蛋白 L27a（RPL27A）基因被认为是与大理石花纹相关的基因的候选基因。在本研究中，在 2 个牛群之间检测到 RPL27A 启动子区域的单核苷酸多态性（SNP），称为 g.3109537C>T。通过对日本黑牛群体的分析，该 SNP 与牛肉大理石花纹标准数量的预测育种值相关。该 SNP 的基因型对皮下脂肪厚度的预测育种值的影响没有统计学意义。这些发现表明，RPL27A SNP 可能有助于有效的标记辅助选择，以增加日本黑牛大理石花纹的水平。
