We also know that even if our DNA is somewhat responsible for increased risks for common diseases, and in some cases is fully responsible for inherited diseases, the environment in which this DNA functions can be as important as the composition of the DNA itself. Indeed, from fertilization on, the environment in which the fertilized egg develops – for example, what the mother eats, whether she smokes or drinks alcohol, and whether she develops diseases or infections – places so-called epigenetic marks on the DNA or on the proteins surrounding it, affecting its function.
我们还知道，即使我们的DNA在某种程度上要为常见疾病风险的增加负责，有时更是遗传病的唯一元凶，但DNA的功能环境与DNA本身的组成一样重要。事实上，从受精开始，受精卵的发育环境——比如母亲吃什么、是否吸烟和饮酒、是否有疾病或受传染——都会给DNA或其周围但被指打上外生基因标记，影响其功能。