Changes in methylation between relapse and diagnosis. Changes in methylation z scores between relapse and diagnosis are shown as box plots. The boxes represent the 25% to 75% interquartile range, horizontal lines inside the boxes show the medians, and vertical bars show the 5% to 95% range. Gray boxes denote a significant increase in methylation in relapse (P < .05, Wilcoxon signed rank test). Mean z score was calculated as the mean of individual gene z scores. All genes showed increase in methylation at relapse with the exception of the LINE-1 repetitive element.