(in Harousseau et al). Hierarchical cluster subgroups are correlated with distinct cytogenetic and molecular genetic abnormalities.

Using normalized expression levels of 4580 genes, a 2-dimensional unsupervised hierarchical clustering analysis was performed on CD138-enriched myeloma cells from 221 newly diagnosed myelomas. The hierarchical clustering was performed using the Average Linkage Clustering with center correlation. Two major cluster branches are created containing Hyperdiploid/CCND1 Low and Normal karyotypes and CCND1 spikes defining another. The other branch consisted of two groups defined by a proliferation signature and the other harboring virtually all MMSET, MF, and MAFB spikes. Cluster groups, designated I, II, III, and IV, are indicated.