Although there was no statistically significant difference between the patient and control groups for the other genes, abnormally high methylation – defined as an increase of the average methylation level beyond that of the average observed in the group of normal tissues plus twice the standard deviation[43] – was a frequent event in patient CLL samples but for DACT1 and DKK4. The gene discussed is DKK4; the disease is B-cell chronic lymphocytic leukemia.