Clustering of myometrial expression profiles with HOPACH. Gene-expression profiles for 27 microarrays (vertical axis) and 4,510 probe sets (horizontal axis) are shown in the context of the HOPACH cluster map (non-pregnant data excluded). The array groups correspond to mid to late gestation (14.5, 16.5, 17.5 and 18.5 days) and postpartum (6 and 24 h). Eight clusters of genes are arranged vertically. Physiological phase groups are assigned on the basis of visual observation and association with previously associated regulators. MAPPFinder results are shown for the top-ranking distinct biological process, molecular function and cellular component groups based on a permuted p-value. Previously associated regulators of uterine quiescence and activation are indicated by a colored line next to the location of the corresponding gene probe set in the cluster map.