So far no expression of HMGI-C in the peripheral blood of healthy controls could be found, which is of advantage, since the specificity of other RT–PCR assays in breast cancer, such as RT–PCR for cytokeratin 19, had to be questioned due to an expression in healthy controls (Bostick et al, 1998; Slade et al, 1999). The gene discussed is KRT19; the disease is breast cancer.