Chakravarti Aravinda
McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205.
Cold Spring Harb Perspect Biol. 2015 Sep 1;7(9):a023358. doi: 10.1101/cshperspect.a023358.
Human populations, however defined, differ in the distribution and frequency of traits they display and diseases to which individuals are susceptible. These need to be understood with respect to three recent advances. First, these differences are multicausal and a result of not only genetic but also epigenetic and environmental factors. Second, the actions of genes, although crucial, turn out to be quite dynamic and modifiable, which contrasts with the classical view that they are inflexible machines. Third, the diverse human populations across the globe have spent too little time apart from our common origin 50,000 years ago to have developed many individually adapted traits. Human trait and disease differences by continental ancestry are thus as much the result of nongenetic as genetic forces.
无论如何定义，人类群体在他们所表现出的性状分布和频率以及个体易患的疾病方面存在差异。需要结合最近的三项进展来理解这些差异。首先，这些差异是多因素造成的，不仅是遗传因素的结果，也是表观遗传和环境因素的结果。其次，基因的作用虽然至关重要，但结果却是相当动态且可改变的，这与传统观点认为基因是固定不变的机器形成了对比。第三，全球不同的人类群体自5万年前的共同起源以来，彼此分离的时间太短，以至于没有形成许多个体适应性性状。因此，按大陆血统划分的人类性状和疾病差异，非遗传力量和遗传力量的作用一样大。
