While several testicular tumour suppressor genes have now been identified (Bartkova et al, 2000; Datta et al, 2001; Luo et al, 2001; Eyzaguirre and Gatalica, 2002; Honorio et al, 2003), only a few, for example RASSF1A (Honorio et al, 2003), MGMT (Smith-Sorensen et al, 2002), have been reported to be silenced in testicular tumours through DNA hypermethylation. The gene discussed is MGMT; the disease is neoplasm of testis.