Epigenetic differences arise during the lifetime of monozygotic twins
Epigenetic differences arise during the lifetime of monozygotic twins
复制标题
DOI：
10.1073/pnas.0500398102
复制
发表时间：
2005-07-26
影响因子：
11.1
通讯作者：
Esteller, M
中科院分区：
文献类型：
--
作者：
Fraga, MF;Ballestar, E;Esteller, M
单卵双胞胎有共同的基因型。然而，大多数同卵双胞胎并不完全相同;可能会观察到几种类型的表型不一致，例如疾病易感性的差异和广泛的拟人化特征。对于这些观察结果有几种可能的解释，但其中之一是表观遗传差异的存在。为了解决这个问题，我们研究了一个大队列的单卵双胞胎的DNA甲基化和组蛋白乙酰化的整体和基因座特异性差异。我们发现，尽管双胞胎在生命的早期在表观遗传学上无法区分，但年龄较大的单卵双胞胎在5-甲基胞嘧啶DNA和组蛋白乙酰化的整体含量和基因组分布方面表现出显着差异，影响了他们的基因表达画像。这些发现表明，在我们理解不同的表型如何起源于相同的基因型时，表观遗传学是如何缺失的。
Monozygous twins share a common genotype. However, most monozygotic twin pairs are not identical; several types of phenotypic discordance may be observed, such as differences in susceptibilities to disease and a wide range of anthropomorphic features. There are several possible explanations for these observations, but one is the existence of epigenetic differences. To address this issue, we examined the global and locus-specific differences in DNA methylation and histone acetylation of a large cohort of monozygotic twins. We found that, although twins are epigenetically indistinguishable during the early years of life, older monozygous twins exhibited remarkable differences in their overall content and genomic distribution of 5-methylcytosine DNA and histone acetylation, affecting their gene-expression portrait. These findings indicate how an appreciation of epigenetics is missing from our understanding of how different phenotypes can be originated from the same genotype.