skin and the esophageal mucosa. Dideoxy sequencing of candidate genes KRIS, ESP, JUP, TP63, and KRTI4 exons I, 4, and 6 (the regions harboring most KRTI4 mutations) was negative. Patient 2 CMH076 was a male born at term with lactic acidosis, cardio- myopathy, and corneal clouding. He was born to a pr