Recent studies suggested that cyclin D2 expression is inhibited by the aberrant methylation of the promoter region of the cyclin D2 gene in breast cancers as well as in Epstein–Barr virus-positive Burkitt's lymphoma (Sinclair et al, 1995; Evron et al, 2001; Lehmann et al, 2002). The gene discussed is CCND2; the disease is breast cancer.