同卵双胞胎来源于同一个受精卵,DNA序列基本一致,但在某些重要表型上如复杂疾病,并不完全一样。利用表型不一致的同卵双胞胎进行研究,能在遗传背景、母体效应、年龄性别效应等一致的基础上,深入研究分析复杂性状的表观调控机制。而DNA甲基化是最为稳定的一类表观遗传修饰。在人类中,利用同卵双胞胎对印记异常疾病、精神类疾病、自身免疫病及癌症等疾病的DNA甲基化调控研究已经揭示了多个致病基因,为研究疾病的表观调控以及表观遗传学药物的应用打下了基础。本文着重对同卵双胞胎DNA甲基化状态、DNA甲基化遗传力计算以及复杂性状DNA甲基化调控的研究应用及其进展展开综述,以期为复杂性状表观调控机制研究提供借鉴和参考。
Coming from a single zygote, monozygotic (MZ) twins share nearly all of their genetic materials and are almost strikingly similar in appearance. Yet they are often discordant for important phenotypes including complex diseases. The study of discordant MZ twins allows us to understand the role of epigenetics in complex traits by con- trolling many potential confounders, such as genetic factors, maternal effects, age and sex. As we know, DNA me- thylation is the most stable epigenetic modification. In human, many causal genes, regulating disease status by DNA methylation modification in imprinting disorders, psychological disorders, autoimmune diseases and cancers, have been discovered, which provides a foundation for studying epigenetic regulation of diseases and application of epigenetic drugs. This article reviews the latest findings on DNA methylation status, estimates of DNA methylationheritability as well as studies of DNA methylation regulation in complex traits using MZ twins, in order to provide reference for research on epigenetic modification in complex traits.