Lipkin E, Fulton J, Cheng H, Yonash N, Soller M
Department of Genetics, The Hebrew University of Jerusalem, Israel.
Poult Sci. 2002 Mar;81(3):283-92. doi: 10.1093/ps/81.3.283.
Many large, half-sib sire families are an integral component of chicken genetic improvement programs. These family structures include a sufficient number of individuals for mapping quantitative trait loci (QTL) at high statistical power. However, realizing this statistical power through individual or selective genotyping is yet too costly to be feasible under current genotyping methodologies. Genotyping costs can be greatly reduced through selective DNA pooling, involving densitometric estimates of marker allele frequencies in pooled DNA samples. When using dinucleotide microsatellite markers, however, such estimates are often confounded by overlapping "shadow" bands and can be confounded further by differential amplification of alleles. In the present study a shadow correction procedure provided accurate densitometric estimates of allele frequency for dinucleotide microsatellite markers in pools made from chicken purified DNA samples, fresh blood samples, and frozen-thawed blood samples. In a retrospective study, selective DNA pooling with thawed blood samples successfully identified two QTL previously shown by selective genotyping to affect resistance in chickens to Marek's disease. It is proposed that use of selective DNA pooling can provide relatively low-cost mapping and use in marker-assisted selection of QTL that affect production traits in chickens.
许多大型半同胞父系家系是鸡遗传改良计划的一个组成部分。这些家系结构包含足够数量的个体，以便以高统计功效定位数量性状位点（QTL）。然而，通过个体或选择性基因分型来实现这种统计功效，在当前的基因分型方法下成本仍然过高，难以可行。通过选择性DNA池化可以大幅降低基因分型成本，这涉及对池化DNA样本中标记等位基因频率的密度测定估计。然而，当使用二核苷酸微卫星标记时，此类估计常常因重叠的“阴影”条带而混淆，并且可能因等位基因的差异扩增而进一步混淆。在本研究中，一种阴影校正程序为从鸡纯化DNA样本、新鲜血液样本和冻融血液样本制成的池中，提供了二核苷酸微卫星标记等位基因频率的准确密度测定估计。在一项回顾性研究中，使用冻融血液样本进行选择性DNA池化成功鉴定出两个QTL，之前通过选择性基因分型已表明它们影响鸡对马立克氏病的抗性。有人提出，使用选择性DNA池化可为影响鸡生产性状的QTL提供相对低成本的定位，并用于标记辅助选择。
