Liu et al. (2009) investigated the methylation status of RASSF1A or DAPK promoter in 28 RB tissues, normal retinal tissues from five donor cadaver eyes, nine peripheral blood samples of RB patients, and normal-peripheral blood samples from five healthy volunteers matched on age and sex by methylation-specific PCR (MSP). The gene discussed is DAPK1; the disease is retinoblastoma.