An introgression analysis of quantitative trait loci that contribute to a morphological difference between Drosophila simulans and D. mauritiana.
An introgression analysis of quantitative trait loci that contribute to a morphological difference between Drosophila simulans and D. mauritiana.
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对导致模拟果蝇和毛里求斯果蝇之间形态差异的数量性状基因座的渗入分析。
DOI：
10.1093/genetics/145.2.339
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发表时间：
1997
期刊：
影响因子：
3.3
通讯作者：
Mercer,JM
中科院分区：
文献类型：
--
作者：
Laurie,CC;True,JR;Liu,J;Mercer,JM
拟果蝇D.毛里求斯在后叶的形态上有明显的不同，后叶是雄性特有的生殖结构。脑叶的大小和形状都可以通过主成分和傅立叶分析得到的形态学变量PC 1来量化。在PC 1种间差异的遗传结构进行了研究，以前的复合区间作图，这主要是加性遗传，与最低的8个数量性状位点（QTL）影响的性状。通过重复回交将毛里求斯第三染色体的标记片段渐渗到模拟背景中，扩展了该分析。这两种类型的实验是一致的，表明第三染色体上的几个QTL可能具有在亲本差异的10-15%范围内的影响，并且所有或几乎所有QTL都具有相同方向的影响。由于亲本差异很大（30.4环境标准差），这种程度的影响可以产生替代纯合子，在表型上几乎没有重叠。然而，这些估计值可能不能反映单个基因座的影响，因为每个区间或渗入片段可能包含多个QTL。等位基因效应的一致方向提示了后叶的定向选择历史。
Drosophila simulansandD. mauritianadiffer markedly in morphology of the posterior lobe, a male-specific genitalic structure. Both size and shape of the lobe can be quantified by a morphometric variable, PC1, derived from principal components and Fourier analyses. The genetic architecture of the species difference in PC1 was investigated previously by composite interval mapping, which revealed largely additive inheritance, with a minimum of eight quantitative trait loci (QTL) affecting the trait. This analysis was extended by introgression of marked segments of themauritianathird chromosome into asimulansbackground by repeated backcrossing. The two types of experiment are consistent in suggesting that several QTL on the third chromosome may have effects in the range of 10–15% of the parental difference and that all or nearly all QTL have effects in the same direction. Since the parental difference is large (30.4 environmental standard deviations), effects of this magnitude can produce alternative homozygotes with little overlap in phenotype. However, these estimates may not reflect the effects of individual loci, since each interval or introgressed segment may contain multiple QTL. The consistent direction of allelic effects suggests a history of directional selection on the posterior lobe.