在医疗实践中,人们经常发现不同的个体对某种药物或对某种外来化学物质的耐受有所不同,即使是同一家族的不同成员,有时也有很大的差异。药物遗传学研究试图弄清不同个体(同卵双生除外)对药物和其它化学物质不同反应的遗传基础。这些反应不仅包括治疗作用如控制疾病的发作,而且也包括副作用如增加药物毒性和致癌的风险。 In medical practice, people often find that different individuals have different tolerance to a certain drug or to some foreign chemical substance, and even different members of the same family sometimes make great differences. Pharmacogenetics studies attempt to understand the genetic basis of different responses to drugs and other chemicals from individuals (except identical twins). These reactions include not only therapies such as controlling seizures, but also side effects such as increasing the risk of drug toxicity and carcinogenesis.