Numerous genetic conditions give rise to a scaly skin phenotype as a result of impaired barrier function. Differences in appearance suggest the response of epidermal cells depends upon the basic defect. The present work characterizes the departure of afflicted corneocytes from normal as judged by their proteomic profiles in three types of autosomal recessive congenital ichthyosis arising from defects in the genes PNPLA1, SDR9C7 and TGM1. The results show that the profiles were distinctive, each displaying a set of altered protein levels, but with a subset of common alterations. Departure from the normal profile was examined at three different anatomic sites (forearm, forehead, leg). Reflecting that the normal protein profile differed at these sites, comparing profiles from afflicted subjects revealed that the alterations in profile were site-dependent. These results suggest proteomic profiling can provide a quantitative measure of departure from the normal state of epidermis. Further development may find application to diagnosis, including identification of new genetic defects, and may help understand signaling pathways perturbed by the basic defects, supplementing visual evaluation of treatment.