CBX4 and cerebrotendinous xanthomatosis: Compared to renal CTX the top inhibited transcriptional regulators in the renal IM were Hnf1a, Lhx1, Cbx4 and Hnf4a, whereas the top activated regulators include Rela, Hif1a and Cdkn2a. Cdkn2a expression in renal IM is higher (Log2 fold change 2.9) compared to CTX and Fig. 7A shows the predicted influence of Cdkn2a on 85 differentially expressed transcripts.