Lamont S J, Lakshmanan N, Plotsky Y, Kaiser M G, Kuhn M, Arthur J A, Beck N J, O'Sullivan N P
Department of Animal Science, Iowa State University, Ames 50011-3150, USA.
Anim Genet. 1996 Feb;27(1):1-8. doi: 10.1111/j.1365-2052.1996.tb01170.x.
This study utilized DNA fingerprints and crosses of two genetically distinct lines of layer-type chickens to identify genetic markers linked to quantitative trait loci (QTL). In phase I, backcross (BC1) hens were separately ranked for each of eight traits and then blood pools were produced in groups along each phenotypic distribution. The DNA was isolated from the blood pools and used in a gradient analysis to screen for DNA fingerprint bands that exhibited intensity gradients associated with the phenotypic traits. To identify linkage of bands with QTL and to estimate band effects, F2 progeny were produced in phase II from the phase I BC1 population. A single-trait animal model was used for analysis of associations of all individual DNA fingerprint bands of sires and their progeny phenotypic performance. Twenty fingerprint bands, only two of which had shown trait-associated gradients in phase I, were identified by the animal model analysis of the progeny test as QTL linked (P < or = 0.05) to specific traits of growth, reproduction and egg quality. These 20 bands warrant further study as potentially valuable molecular markers for QTL.
本研究利用两个遗传上不同品系的蛋用型鸡的DNA指纹图谱和杂交，来鉴定与数量性状基因座（QTL）连锁的遗传标记。在第一阶段，对回交（BC1）母鸡的八个性状分别进行排名，然后沿着每个表型分布将其分组建立血池。从血池中提取DNA，并用于梯度分析，以筛选出与表型性状相关的强度梯度的DNA指纹条带。为了鉴定条带与QTL的连锁关系并估计条带效应，在第二阶段从第一阶段的BC1群体中产生F2后代。使用单性状动物模型分析父本的所有个体DNA指纹条带与其后代表型表现之间的关联。通过后代测试的动物模型分析，鉴定出20个指纹条带与生长、繁殖和蛋品质等特定性状的QTL连锁（P≤0.05），其中只有两个条带在第一阶段显示出与性状相关的梯度。这20个条带作为QTL潜在有价值的分子标记值得进一步研究。
