Hierarchic 2-way clustering of normal, MDS, and non-MDS anemia CD34⁺ cells using the predictive probe sets defined by neighborhood analysis. The initial data set of 14 low-risk MDS and 9 healthy controls was used in addition to that from 5 patients with non-MDS causes of anemia. Horiziontal clustering is by sample, and vertical clustering is by gene expression. Red bars indicate overexpression; green, underexpression; the vertical blue bar, the position of the lymphoid progenitor gene cluster.