Dyskeratosis congenita is a bone marrow failure syndrome classically characterized by the triad of abnormal skin pigmentation, nail dystrophy, and leukoplakia of the oral mucosa. Progressive bone marrow failure occurs in over 80% of cases and is the main cause of early mortality. The phenotype is highly variable, and affected individuals may have multiple additional features, including pulmonary fibrosis, liver cirrhosis, premature hair loss and/or graying, osteoporosis, atresia of the lacrimal ducts, and learning difficulties. Predisposition to malignancy is an important feature. The disorder is caused by defects in the maintenance of telomeres. [From OMIM]