Two XP patients are presented. A corneal perforation in the left eye of the first patient necessitated an at-random transplantation à chaud. The graft was remarkably well tolerated, which is possibly explained by UV-light-induced suppression of the cellular immune response in the patient. The right eye of this patient and both eyes of the second patient had a keratoconus. Keratoconus in XP may be the result of disturbances in the cell differentiation and the function of epithelial cells and keratocytes, due to UV-light-induced deficient DNA repair synthesis.