The presence of distinct prominin-1 splicing variants in neural stem cells, oligodendrocytes, and astrocytes, which suggests related but distinct functions (5, 23, 30), adds complexity to the analysis of the origin of neural cancer cells notably by immunohistochemistry, as prominin-1 splice variants may differentially mark cell subpopulations in glioma. The gene discussed is PROM1; the disease is central nervous system cancer.