Finally, to determine whether rs45446698 genotype could affect patient outcome by influencing metabolism of cytotoxic agents that are CYP3A substrates,15 we tested for the association between rs45446698 genotype and 10-year breast cancer-specific survival in 91,539 breast cancer cases from 71 studies for whom follow-up data were available. The gene discussed is CYP3A4; the disease is breast cancer.