第六章 表观遗传学(epigenetics )x x马骡驴骡骡子更象谁?表观遗传学主要内容:第一节表观遗传概述第二节表观遗传调控机制第三节表观遗传研究的应用第一节表观遗传概述一、表观遗传现象 分子生物学的中心法则(entral dogma)碱基序列(基因)决定性状,序列改变,引起性状的改变。影响基因表达的遗传变异因素l基因突变(错义突变)l基因缺失/倍增l染色体结构及数目变异问题:基因表达的变化(或性状的变化)一定是DNA序列变异的结果吗?BUT “Some authors use the term “variation” in a technical sense, as implying a modification directly due to the physical conditions of life; and “variations” in this sense are supposed not to be inherited; but who can say that the dwarfed condition of shells in the brackish wat