Bi-directional hierarchical cluster analysis of gene expression changes. Green indicates down-regulation relative to control and red indicates up-regulation relative to control. Fathead minnows were exposed to (A) 50 ng EE2/L (EE2), 100 ng ZM/L (ZM), a mixture of 50 ng EE2/L and 100 ng ZM/L (Mix), or TEG control (Cntrl). Array analysis was on the 2 K array. (B) 5 ng EE2/L (EE2), a mixture of 5 ng EE2/L with 100 ng ZM/L (EE2/ZM) or TEG control (Cntrl). Array analysis was on the 22 K array. Top, clustering was performed by treatment; side, clustering was performed by gene. Each column represents a different array.