de Koning D J, Cabrera C P, Haley C S
The Roslin Institute, Roslin Biocentre, Roslin, EH25 9PS, United Kingdom.
Poult Sci. 2007 Jul;86(7):1501-9. doi: 10.1093/ps/86.7.1501.
Microarrays have been widely implemented across the life sciences, although there is still debate on the most effective uses of such transcriptomics approaches. In genetical genomics, gene expression measurements are treated as quantitative traits, and genome regions affecting expression levels are denoted as expression QTL (eQTL). The detected eQTL can represent a locus that lies close to the gene that is being controlled (cis-acting) or one or more loci that are unlinked to the gene that is being controlled (trans-acting). One powerful outcome of genetical genomics is the reconstruction of genetic pathways underlying complex trait variation. Because of the modest size of experiments to date, genetical genomics may fall short of its promise to unravel genetic networks. We propose to combine expression studies with fine mapping of functional trait loci. This synergistic approach facilitates the implementation of genetical genomics for species without inbred resources but is equally applicable to model species. Among livestock species, poultry is well placed to embrace this technology with the availability of the chicken genome sequence, microarrays for various platforms, as well as experimental populations in which QTL have been mapped. In the buildup toward full-blown eQTL studies, we can study the effects of known candidate genes or marked QTL at the gene expression level in more focused studies. To demonstrate the potential of genetical genomics, we have identified the cis and trans effects for a functional BW QTL on chicken chromosome 4 in breast tissue samples from chickens with contrasting QTL genotypes.
微阵列技术已在生命科学领域广泛应用，尽管对于此类转录组学方法的最有效用途仍存在争议。在遗传基因组学中，基因表达测量被视为数量性状，影响表达水平的基因组区域被称为表达数量性状基因座（eQTL）。检测到的eQTL可以代表一个与受调控基因紧密相邻的位点（顺式作用），或者一个或多个与受调控基因不连锁的位点（反式作用）。遗传基因组学的一个重要成果是重建复杂性状变异背后的遗传途径。由于迄今为止实验规模有限，遗传基因组学可能无法完全实现其揭示遗传网络的承诺。我们建议将表达研究与功能性状基因座的精细定位相结合。这种协同方法有助于在没有近交资源的物种中实施遗传基因组学，同时也同样适用于模式物种。在家畜物种中，家禽由于有鸡基因组序列、各种平台的微阵列以及已定位QTL的实验群体，非常适合采用这项技术。在全面开展eQTL研究的过程中，我们可以在更有针对性的研究中，在基因表达水平上研究已知候选基因或标记QTL的效应。为了证明遗传基因组学的潜力，我们在具有不同QTL基因型的鸡的胸肌组织样本中，确定了鸡4号染色体上一个功能性体重QTL的顺式和反式效应。
