CYP1A1 and Dysmenorrhea: Moreover, the CYP1A1 MspI variant GENE C/C6235 or the CYP1A1 HincII wild gene Ile/Ile462 was found in the DNA test of women with passive smoking exposure, which reduced their ability to convert toxic metabolites in cigarette smoke into less harmful hydrophilic compounds and significantly increased the risk of dysmenorrhea.