Serman Alan, Vlahović Maja, Serman Ljiljana, Bulić-Jakus Floriana
General Hospital Sveti Duh, Zagreb, Croatia.
Coll Antropol. 2006 Sep;30(3):665-71.
Epigenetics refers to the study of heritable changes in gene expression that occur without a change in DNA sequence. In the last decade, it has been shown that epigenetic mechanisms provide an "extra" layer of transcriptional control that regulates genes expression. Three distinct mechanisms appear intricately related in initiating and sustaining epigenetic modifications: RNA-associated silencing, DNA methylation and histone modification. These mechanisms are critical components in the normal development and cell growth. DNA methylation is involved in transcriptional silencing of genes, regulation of expression of imprinted genes, a number of tumour suppressor genes in cancer and silencing of genes located on the inactive X chromosome. In this review, we are focused on the basic principles of DNA methylation as the main epigenetic mechanism for normal embryonic development and epigenetic alterations that contribute to carcinogenesis.
表观遗传学是指对基因表达中可遗传变化的研究，这些变化发生在DNA序列无变化的情况下。在过去十年中，研究表明表观遗传机制提供了一层“额外”的转录控制，调节基因表达。三种不同的机制在启动和维持表观遗传修饰方面似乎有着复杂的关联：与RNA相关的沉默、DNA甲基化和组蛋白修饰。这些机制是正常发育和细胞生长的关键组成部分。DNA甲基化参与基因的转录沉默、印记基因表达的调控、癌症中一些肿瘤抑制基因的调控以及位于失活X染色体上基因的沉默。在本综述中，我们重点关注DNA甲基化作为正常胚胎发育的主要表观遗传机制以及促成致癌作用的表观遗传改变的基本原理。
