School of Agriculture, Food and Wine, University of Adelaide, Roseworthy SA 5371 Australia.
Anim Genet. 2010 Jun;41(3):253-9. doi: 10.1111/j.1365-2052.2009.01990.x. Epub 2009 Nov 26.
beta, beta-carotene-9', 10'-dioxygenase (BCO2) plays a role in cleaving beta-carotene eccentrically, and may be involved in the control of adipose and milk colour in cattle. The bovine BCO2 gene was sequenced as a potential candidate gene for a beef fat colour QTL on chromosome (BTA) 15. A single nucleotide base change located in exon 3 causes the substitution of a stop codon (encoded by the A allele) for tryptophan(80) (encoded by the G allele) (c. 240G>A, p.Trp80stop, referred to herein as SNP W80X). Association analysis showed significant differences in subcutaneous fat colour and beta-carotene concentration amongst cattle with different BCO2 genotypes. Animals with the BCO2 AA genotype had more yellow beef fat and a higher beta-carotene concentration in adipose tissues than those with the GA or GG genotype. QTL mapping analysis with the BCO2 SNP W80X fitted as a fixed effect confirmed that this SNP is likely to represent the quantitative trait nucleotide (QTN) for the fat colour-related traits on BTA 15. Moreover, animals with the AA genotype had yellower milk colour and a higher concentration of beta-carotene in the milk.
β，β-胡萝卜素-9'，10'-加双氧酶（BCO2）在β-胡萝卜素的偏心裂解中起作用，并且可能参与牛的脂肪和牛奶颜色的控制。牛 BCO2 基因被测序为染色体（BTA）15 上牛肉脂肪颜色 QTL 的潜在候选基因。位于外显子 3 中的单个核苷酸碱基变化导致终止密码子（由 A 等位基因编码）取代色氨酸（80）（由 G 等位基因编码）（c.240G>A，p.Trp80stop，在此称为 SNP W80X）。关联分析显示，不同 BCO2 基因型的牛的皮下脂肪颜色和β-胡萝卜素浓度存在显著差异。与 GA 或 GG 基因型相比，具有 BCO2AA 基因型的动物具有更黄的牛肉脂肪和更高的脂肪组织中β-胡萝卜素浓度。用 BCO2 SNP W80X 作为固定效应进行的 QTL 映射分析证实，该 SNP 可能代表 BTA 15 上与脂肪颜色相关性状的数量性状核苷酸（QTN）。此外，具有 AA 基因型的动物的牛奶颜色更黄，牛奶中的β-胡萝卜素浓度更高。
