High-resolution targeted bisulfite sequencing reveals blood cell type-specific DNA methylation patterns in IL13 and ORMDL3.

Söderhäll C, Reinius LE, Salmenperä P, Gentile M, Acevedo N, Konradsen JR, Nordlund B, Hedlin G, Scheynius A, Myllykangas S, Kere J

Clin Epigenetics 13 (1) 106 [2021-05-10; online 2021-05-10]

Methylation of DNA at CpG sites is an epigenetic modification and a potential modifier of disease risk, possibly mediating environmental effects. Currently, DNA methylation is commonly assessed using specific microarrays that sample methylation at a few % of all methylated sites. To understand if significant information on methylation can be added by a more comprehensive analysis of methylation, we set up a quantitative method, bisulfite oligonucleotide-selective sequencing (Bs-OS-seq), and compared the data with microarray-derived methylation data. We assessed methylation at two asthma-associated genes, IL13 and ORMDL3, in blood samples collected from children with and without asthma and fractionated white blood cell types from healthy adult controls. Our results show that Bs-OS-seq can uncover vast amounts of methylation variation not detected by commonly used array methods. We found that high-density methylation information from even one gene can delineate the main white blood cell lineages. We conclude that high-resolution methylation studies can yield clinically important information at selected specific loci missed by array-based methods, with potential implications for future studies of methylation-disease associations.

PubMed 33971943

DOI 10.1186/s13148-021-01093-7

Crossref 10.1186/s13148-021-01093-7

pmc: PMC8111952
pii: 10.1186/s13148-021-01093-7