For example, scientists have known for decades that certain drugs can cause severe and precipitous anemia in people with a genetic deficiency of the enzyme G6PD. More recently, researchers have learned that certain cancer drugs are ineffective in fighting tumors containing the mutated variant of the gene KRAS.
这算不上什么新方法。比方说，几十年来科学家一直知道某些药物可能在G6PD酶缺乏的遗传缺陷者身上引发严重的急性贫血。最近研究人员又发现某些癌症药物在对抗含KRAS基因变异的肿瘤时没有效果。