Methylomic Analysis of Nasal Brushings in Pediatric Acute Respiratory Distress Syndrome: A Pilot Study

To determine whether the nasal epithelial methylome identifies subgroups of PARDS, we profiled genome-wide DNA methylation in nasal brushings from 21 children with PARDS and 3 pediatric ICU controls using the Infinium MethylationEPIC v2.0 array. After estimating and adjusting for cell-type composition, we performed unsupervised clustering and cell-type-specific differential methylation analysis.

Cellular composition explained the majority of variation in the unadjusted methylome, and composition-adjusted clustering yielded only weak subgroup structure. These data indicate that, at this sample size, the nasal methylome does not identify PARDS subgroups.