Biosciences Research Division, Department of Primary Industries Victoria, Melbourne, Victoria, Australia.
PLoS One. 2009 Aug 18;4(8):e6676. doi: 10.1371/journal.pone.0006676.
Continued production of food in areas predicted to be most affected by climate change, such as dairy farming regions of Australia, will be a major challenge in coming decades. Along with rising temperatures and water shortages, scarcity of inputs such as high energy feeds is predicted. With the motivation of selecting cattle adapted to these changing environments, we conducted a genome wide association study to detect DNA markers (single nucleotide polymorphisms) associated with the sensitivity of milk production to environmental conditions. To do this we combined historical milk production and weather records with dense marker genotypes on dairy sires with many daughters milking across a wide range of production environments in Australia. Markers associated with sensitivity of milk production to feeding level and sensitivity of milk production to temperature humidity index on chromosome nine and twenty nine respectively were validated in two independent populations, one a different breed of cattle. As the extent of linkage disequilibrium across cattle breeds is limited, the underlying causative mutations have been mapped to a small genomic interval containing two promising candidate genes. The validated marker panels we have reported here will aid selection for high milk production under anticipated climate change scenarios, for example selection of sires whose daughters will be most productive at low levels of feeding.
在未来几十年里，继续在预计受气候变化影响最大的地区（如澳大利亚的奶制品养殖区）生产食物将是一个重大挑战。除了气温上升和水资源短缺外，预计还会出现诸如高能饲料等投入品的短缺。为了选择适应这些变化环境的牛，我们进行了全基因组关联研究，以检测与牛奶产量对环境条件的敏感性相关的 DNA 标记（单核苷酸多态性）。为此，我们将历史牛奶产量和天气记录与澳大利亚广泛的生产环境中许多奶牛的奶牛父亲的密集标记基因型相结合。分别在两个独立的群体中验证了与牛奶产量对饲养水平的敏感性和牛奶产量对温度湿度指数的敏感性相关的标记，其中一个群体是不同的牛品种。由于牛品种之间的连锁不平衡程度有限，潜在的致病突变已被映射到一个包含两个有希望的候选基因的小基因组间隔区。我们在这里报告的经过验证的标记面板将有助于在预期的气候变化情景下选择高牛奶产量，例如选择其女儿在低饲养水平下生产力最高的父亲。
