Fig. 3: Exploratory analysis of low-level H19/ICR1 hypermethylation detectable in peripheral blood.

a Patients from the current study COG cohort with BWT containing 11p15.5 LOI were found to have a statistically significant increase in 11p15.5 H19/ICR1 methylation detected in the peripheral blood when compared to patients with tumors having 11p15.5 retention of imprinting (unpaired, two-tailed t test p = 0.0210; n = 50 biologically independent samples). b 11p15.5 LOI was often detectable above the threshold value (β > 0.7) for loss of imprinting in adjacent non-diseased kidney tissues (n = 29 biologically independent samples). c No differences were detected among patient groups at 11p15.5 KCNQ1OT1/ICR2 in peripheral blood (n = 50 biologically independent samples). Of note, the single sample outlier with tumor 11p15.5 LOH, hypermethylation at H19/ICR1, and hypomethylation at KCNQ1OT1/ICR2 detected in the peripheral blood was confirmed to have mosaicism for 11p15.5 LOH detected in peripheral blood by whole genome sequencing. For (a–c), lines represent median values. d A significant increase in H19/ICR1 methylation detected in peripheral blood was noted when BWT patients (n = 78) were compared to unilateral WT (n = 154 biologically independent samples) and healthy community control subjects (n = 282 biologically independent samples; p values are ordinary one-way ANOVA with pairwise values corrected for multiple comparisons). 26 BWT patient blood samples (green triangles; n = 20 biologically independent from current study, n = 6 from survivor cohort) had low-level H19/ICR1 gain of methylation defined as a β value greater than two standard deviations (2 SD) above the mean from the healthy community control cohort. For boxes in (d), measure of center lines are mean and whiskers are SD. LOH loss of heterozygosity, LOI loss of imprinting. Source data are available in the Source Data File.