Cooperative Research Centre for Beef Genetic Technologies, CSIRO Livestock Industries, Queensland Bioscience Precinct, 306 Carmody Road, St. Lucia, Qld, 4067, Australia.
Anim Genet. 2012 Dec;43(6):785-9. doi: 10.1111/j.1365-2052.2012.02330.x. Epub 2012 Feb 27.
Variation in the XK, Kell blood group complex subunit-related family, member 4 (XKR4) gene on BTA14 was associated with rump fat thickness in a recent genome-wide association study. This region is also of interest because it is known to show evidence of a signature of population genetic selection. In this study, additional variation in this gene was genotyped in a sample of a total of 1283 animals of the Belmont Red (BEL) and Santa Gertrudis (SGT) breeds. The SNP rs41724387 was significantly (P < 0.001) associated with rump fat thickness and explained 5.9% of the genetic variance for the trait in this sample. Using the 4466 genotypes for the SNP rs42646708 from several data sets to estimate effects in seven breeds, this relatively large quantitative trait locus effect appears to be a result of the variation in indicine and taurine-indicine composite cattle. However, the only DNA variant found in Brahman cattle that altered the predicted amino acid sequence of XKR4 was not associated with rump fat thickness. This suggests that causative mutations lie outside the coding sequence of this gene.
XK、Kell 血型复合体亚单位相关家族成员 4（XKR4）基因在 BTA14 上的变异与最近的全基因组关联研究中的臀部脂肪厚度有关。该区域也很有趣，因为它被认为显示了种群遗传选择的特征的证据。在这项研究中，在总共 1283 头 Belmont Red（BEL）和 Santa Gertrudis（SGT）品种的样本中对该基因的其他变异进行了基因分型。SNP rs41724387 与臀部脂肪厚度显著相关（P < 0.001），并解释了该样本中该性状遗传变异的 5.9%。使用来自多个数据集的 SNP rs42646708 的 4466 个基因型来估计七个品种的效应，这种相对较大的数量性状位点效应似乎是印度牛和瘤牛-印度牛复合牛的变异的结果。然而，在婆罗门牛中发现的唯一改变 XKR4 预测氨基酸序列的 DNA 变体与臀部脂肪厚度无关。这表明致病突变位于该基因的编码序列之外。
