Dyskeratosis Congenita: Clinical Phenotype and Genetic Features in a Sibling Pair.

Dyskeratosis congenita (DC) is a rare, inherited bone marrow failure syndrome resulting from mutations in genes responsible for telomere maintenance. We report a familial case of DC in two brothers, who exhibited the classic diagnostic triad of reticulate skin pigmentation, oral leukoplakia, and nail dystrophy. Genetic analysis identified a rare, hemizygous missense mutation (c.92A>C, p.Gln31Pro) in the DKC1 gene. This case underscores the variable expressivity of DKC1 mutations and reinforces the importance of recognizing the characteristic mucocutaneous features for timely diagnosis and management of this multisystem disorder.