ERCC2 and Cowden syndrome 1: Other mouse models, including TTD mice bearing the XPD R722W mutation identified in patients with TTD and XPCS mice with the G602D mutation found in patients with XP/CS, partially recapitulated the symptoms of TTD or XP/CS, such as premature aging, brittle hair, cachexia, UV-hypersensitivity and cancer predisposition (Andressoo et al., 2006; de Boer et al., 1998, 2002).