Supportive features included the histologic finding of eosinophilic spongiosis, which is seen in early pemphigoid and pemphigus lesions; a supportive indirect immunofluorescence test; elevated anti-BP230 ELISA at 3 times the upper limit of normal; and a dramatic response to potent topical steroid therapy with a corresponding reduction of anti-BP230 ELISA titers. This evidence concerns the gene DST and pemphigus.