By subjecting BRCA1a, their corresponding Mut#1 K109R, and cancer-predisposing Mut#4 C61G to colony suppression assays using ovarian cancer cells, we were able to show the requirement of Ubc9 binding on the growth suppressor function of BRCA1a proteins in ovarian cancer cells [16]. The gene discussed is UBE2I; the disease is ovarian cancer.