Incline Village, Nev—Part of the difficulty in identifying cancer susceptibility genes is that subtle genetic changes—such as the alteration of a single nucleotide in a gene—can determine whether the gene will predispose an individual to developing cancer. At the same time, these single nucleotide polymorphisms (SNPs) can alter gene function in ways that affect response to therapy or chemoprophylaxis.
That appears to be the case for variants of a gene called SRD5A2, which encodes steroid type 2 5-alpha-reductase, an enzyme that catalyzes the conversion of testosterone to dihydrotestosterone (DHT), reported scientists at an American Association for Cancer Research conference on "Genetic Modifiers of Cancer Susceptibility."
Stephenson J. As Genes Differ, So Should Interventions for Cancer. JAMA. 2001;285(14):1829-1830. doi:10.1001/jama.285.14.1829-JMN0411-3-1