Jablonka Eva, Lamb Marion J
Edelstein Center for the History and Philosophy of Science, Technology and Medicine, Hebrew University, Givat-Ram, Jerusalem 91904, Israel and.
Biology Department, Birkbeck College, University of London, Malet Street, London WC1E 7HX, UK.
Int J Epidemiol. 2015 Aug;44(4):1094-103. doi: 10.1093/ije/dyv020. Epub 2015 Apr 7.
There is evidence that the functional history of a gene in one generation can influence its expression in the next. In somatic cells, changes in gene activity are frequently associated with changes in the pattern of methylation of the cytosines in DNA; these methylation patterns are stably inherited. Recent work suggests that information about patterns of methylation and other epigenetic states can also be transmitted from parents to offspring. This evidence is the basis of a model for the inheritance of acquired epigenetic variations. According to the model, an environmental stimulus can induce heritable chromatin modifications which are very specific and predictable, and might result in an adaptive response to the stimulus. This type of response probably has most significance for adaptive evolution in organisms such as fungi and plants, which lack distinct segregation of the soma and germ line. However, in all organisms, the accumulation of specific and random chromatin modifications in the germ line may be important in speciation, because these modifications could lead to reproductive isolation between populations. Heritable chromatin variations may also alter the frequency and distribution of classical mutations and meiotic recombination. Therefore, inherited epigenetic changes in the structure of chromatin can influence neo-Darwinian evolution as well as cause a type of "Lamarckian" inheritance.
有证据表明，一个基因在一代中的功能历史会影响其在下一代中的表达。在体细胞中，基因活性的变化常常与DNA中胞嘧啶甲基化模式的改变相关联；这些甲基化模式能够稳定遗传。近期研究表明，有关甲基化模式及其他表观遗传状态的信息也能从亲代传递给子代。这一证据构成了获得性表观遗传变异遗传模型的基础。根据该模型，环境刺激可诱导出非常特异且可预测的可遗传染色质修饰，这可能会引发对该刺激的适应性反应。这种反应类型可能对真菌和植物等缺乏体细胞与生殖细胞明显分离的生物体的适应性进化最为重要。然而，在所有生物体中，生殖细胞中特定且随机的染色质修饰的积累在物种形成中可能很重要，因为这些修饰可能导致种群间的生殖隔离。可遗传的染色质变异也可能改变经典突变和减数分裂重组的频率及分布。因此，染色质结构中可遗传的表观遗传变化既能影响新达尔文进化，也能导致一种“拉马克式”遗传。
