The genetic sequence of those infected confers a disposition to certain diseases and also explains why certain therapies are less effective in specific individuals and why some patients suffer unusual or extreme side effects.
被感染者的基因序列使其容易患上某种疾病，也可解释为什么某些疗法对特定的人不大有效以及为什么某些病人有异常或极严重的副作用。