FIGURE 1.

Methylation profiling on peripheral blood leukocytes separates distinct subsets of MDS from normals. Methylation profiles generated by the HELP assay were used to cluster 21 MDS and 9 control samples by hierarchical clustering. The controls formed a cluster that was distinct from MDS samples. The MDS samples included two clusters (groups 1 and 2) of epigenetically similar samples with a greater amount of resemblance to controls. The remaining seven MDS samples demonstrated greater heterogeneity. No correlation with cytogenetics (normal represented as green and abnormal as red) was seen.