As the loss of one copy of chromosome 3 (monosomy 3),which is found in about half of these tumours, is tightly associated with metastaticdisease, a special emphasis was laid on genes located on this chromosome, includingthe fragile histidine triad (FHIT), von Hippel–Lindau (VHL), β-catenin (CTNNB1),activated leukocyte cell adhesion molecule (ALCAM) and retinoic acid receptor-β2(RARB) genes. The gene discussed is RARB; the disease is neoplasm.