In a US cohort of patients with BC, triple-negative breast cancer (TNBC), characterized by a lack of ER, PR, and HER2 receptors,34 was found in 10% to 20% of newly diagnosed patients and was associated with poor outcomes.35 African patients with BC have been reported to be two to three times more likely to have TNBC than patients of European ancestry.36,37 However, in our recent Soweto (Johannesburg, South Africa) study, only 20.7% of black women had TNBC.38,39 Large-scale molecular subtyping studies of BC have been conducted, but mainly in US populations. The gene discussed is ESR1; the disease is breast cancer.