Acrokeratosis Verruciformis of Hopf Showing P602L Mutation in ATP2A2 and Overlapping Histopathological Features With Darier DiseaseBergman, Reuven MD; Sezin, Tanya BA; Indelman, Margarita MSc; Helou, Wissam Abo MD; Avitan-Hersh, Emily MDAmerican Journal of Dermatopathology: August 2012 - Volume 34 - Issue 6 - p 597–601 doi: 10.1097/DAD.0b013e31823f9194 Original Study Abstract Author Information Abstract Abstract: The relationship between acrokeratosis verruciformis (AKV) of Hopf and Darier disease (DD) has been debated for several decades. Both diseases are now thought to result from mutations in the same gene, that is, the ATP2A2 gene encoding the sarco (endo) plasmic reticulum Ca2+ ATPase2 pump (SERCA2), although their histopathological features are different. We sought to detect possible overlapping histopathological features between AKV and DD. Fourteen members of a family affected by AKV were analyzed for the underlying molecular genetic derangement, and 3 cases were studied histopathologically using multiple step sections. A heterozygous P602L mutation in ATP2A2 was identified as the underlying cause in this family. This mutation and a heterozygous A698V were previously described in AKV. Both mutations were not among the 162 mutations in ATP2A2, which were reported to date in DD. The histopathological study demonstrated in several consecutive step sections of 2 of the 3 studied cases, foci of small suprabasal clefts with acantholytic keratinocytes, some of which were mildly dyskeratotic. These focal features were reminiscent of the basic histopathological characteristics of DD. These shared histopathological features of AKV with DD suggest that AKV and DD are allelic disorders with variable expression of the same disease, although identical mutations in ATP2A2 in AKV and DD were not reported to date. Author Information Department of Dermatology, Rambam Medical Center, Bruce Rappaport Faculty of Medicine, Technion Israel Institute of Technology, Haifa, Israel. The authors declare no conflicts of interest. Reprints: Reuven Bergman, MD, Department of Dermatology, Rambam Medical Center, Bruce Rappaport Faculty of Medicine, Technion Israel Institute of Technology, POB 9602, Haifa 31096, Israel (e-mail: firstname.lastname@example.org). © 2012 Lippincott Williams & Wilkins, Inc.