A gene may blunt a breast cancer drug.

A genetic variant commonly found in some Africans may reduce the effectiveness of the breast cancer drug tamoxifen. This variant causes cells to produce a slower version of the enzyme that activates tamoxifen, resulting in lower levels of the active drug in the bloodstream. This could lead to insufficient treatment for patients with two copies of the variant. While genetic screening for this variant may be costly, the study suggests that larger starting doses of tamoxifen could be tested in heavily affected groups. The findings could potentially improve timely care for breast cancer patients in Africa, where access to screenings and treatment is often limited. [Extracted from the article]