Department of Cell and Molecular Biology, Uppsala University, Uppsala, Sweden.
PLoS Genet. 2012;8(8):e1002839. doi: 10.1371/journal.pgen.1002839. Epub 2012 Aug 2.
The phenotypic effect of a gene is normally described by the mean-difference between alternative genotypes. A gene may, however, also influence the phenotype by causing a difference in variance between genotypes. Here, we reanalyze a publicly available Arabidopsis thaliana dataset [1] and show that genetic variance heterogeneity appears to be as common as normal additive effects on a genomewide scale. The study also develops theory to estimate the contributions of variance differences between genotypes to the phenotypic variance, and this is used to show that individual loci can explain more than 20% of the phenotypic variance. Two well-studied systems, cellular control of molybdenum level by the ion-transporter MOT1 and flowering-time regulation by the FRI-FLC expression network, and a novel association for Leaf serration are used to illustrate the contribution of major individual loci, expression pathways, and gene-by-environment interactions to the genetic variance heterogeneity.
基因的表型效应通常通过不同基因型之间的均值差异来描述。然而，基因也可能通过引起基因型之间方差的差异来影响表型。在这里，我们重新分析了一个公开的拟南芥数据集[1]，并表明遗传方差异质性在全基因组范围内似乎与正常加性效应一样常见。该研究还提出了一种理论来估计基因型之间方差差异对表型方差的贡献，并用该理论表明单个基因座可以解释超过 20%的表型方差。两个研究得很好的系统，即离子转运蛋白 MOT1 对钼水平的细胞控制和 FRI-FLC 表达网络对开花时间的调节，以及一个新的叶锯齿关联，用于说明主要单个基因座、表达途径和基因-环境相互作用对遗传方差异质性的贡献。
