DNA methylome analysis of acute lymphoblastic leukemia cells reveals stochastic de novo DNA methylation in CpG islands

• Aim: To identify regions of aberrant DNA methylation in acute lymphoblastic leukemia (ALL) cells of different subtypes on a genome-wide scale. Materials & methods: Whole-genome bisulfite sequencing (WGBS) was used to determine the DNA methylation levels in cells from four pediatric ALL patients of different subtypes. The findings were confirmed by 450k DNA methylation arrays in a large patient set. Results: Compared with mature B or T cells WGBS detected on average 82,000 differentially methylated regions per patient. Differentially methylated regions are enriched to CpG poor regions, active enhancers and transcriptional start sites. We also identified approximately 8000 CpG islands with variable intermediate DNA methylation that seems to occur as a result of stochastic de novo methylation. Conclusion: WGBS provides an unbiased view and novel insights into the DNA methylome of ALL cells.

Subject headings

Medical and Health Sciences  (hsv)

Basic Medicine  (hsv)

Medical Genetics  (hsv)

Medicin och hälsovetenskap  (hsv)

Medicinska grundvetenskaper  (hsv)

Medicinsk genetik  (hsv)

Keyword

acute lymphoblastic leukemia

CpG islands

DNA methylation

epigenome

methylome

whole-genome bisulfite sequencing