Plant Biology Laboratory, The Salk Institute for Biological Studies, La Jolla, CA 92037, USA.
Science. 2011 Oct 21;334(6054):369-73. doi: 10.1126/science.1212959. Epub 2011 Sep 15.
Epigenetic information, which may affect an organism's phenotype, can be stored and stably inherited in the form of cytosine DNA methylation. Changes in DNA methylation can produce meiotically stable epialleles that affect transcription and morphology, but the rates of spontaneous gain or loss of DNA methylation are unknown. We examined spontaneously occurring variation in DNA methylation in Arabidopsis thaliana plants propagated by single-seed descent for 30 generations. We identified 114,287 CG single methylation polymorphisms and 2485 CG differentially methylated regions (DMRs), both of which show patterns of divergence compared with the ancestral state. Thus, transgenerational epigenetic variation in DNA methylation may generate new allelic states that alter transcription, providing a mechanism for phenotypic diversity in the absence of genetic mutation.
表观遗传信息可能会影响生物体的表型，它可以以胞嘧啶 DNA 甲基化的形式被储存和稳定遗传。DNA 甲基化的改变可以产生减数分裂稳定的表观等位基因，从而影响转录和形态，但 DNA 甲基化自发获得或丢失的速率尚不清楚。我们通过单种子繁殖对拟南芥植物进行了 30 代的繁殖，研究了 DNA 甲基化的自发变异。我们鉴定出了 114287 个 CG 单甲基化多态性和 2485 个 CG 差异甲基化区域（DMR），与祖先状态相比，它们都表现出了分化模式。因此，DNA 甲基化的跨代表观遗传变异可能会产生改变转录的新等位基因状态，为没有遗传突变的表型多样性提供了一种机制。
