Timofeeva et al. conducted a case-control study (638 Caucasian patients under the age of 51 with primary lung cancer and 1,300 cancer-free control individuals) and examined the effect of 13 polymorphisms in the CYP1A1, CYP1B1, CYP2A13, CYP3A4 and CYP3A5 genes [24]. The gene discussed is CYP1A1; the disease is lung cancer.