In apparent contrast with the relatively low percentage of ALDH+ breast cancers in vivo, Charafe-Jauffret et al. [46] reported that 23 of 33 cell lines derived from normal and malignant mammary tissue contained an ALDEFLUOR+ population that displayed stem cell properties in vitro and in NOD/SCID xenografts. The gene discussed is LDHA; the disease is breast carcinoma.