DNA methylation at CpG+223 segregates patients with different clinical outcome using a potentially biologically meaningful cutoff of 20%. (A) Kaplan-Meier curves illustrate the time from diagnosis to first treatment of patients who have CLL cells with lower levels of methylation (<20%) compared with those patients who have CLL cells with higher levels of methylation (≥20%). (B) Kaplan-Meier curves illustrate the overall survival duration of patients who have CLL cells with lower vs higher levels of methylation.