In contrast, induction levels of UNC-45A, CHIP, and p23 remain unchanged, while levels of NASP, Aha1, and FKBP51 are induced.42, 121, 125 Whether the differences in chaperone and co-chaperone protein levels seen between AD and nondiseased cells play a role in promoting disease or whether these are changes in response to disease remains an open question. This evidence concerns the gene FKBP4 and Alzheimer disease.