CYP1A1 and carcinoma of esophagus: Recently, Wang et al (2002) genotyped 127 oesophageal cancer cases and 101 controls and found that individuals with the CYP1A1 Val/Val genotype had a higher risk of developing oesophageal cancer than those with Ile/Ile (OR=2.48, 95%CI=1.12–5.54).