Etiologic heterogeneity in dyskeratosis congenita.

Most patients with dyskeratosis congenita [DC or Zinsser-Cole-Engman syndrome] are males hemizygous for an X-linked recessive mutation. However, one or more autosomal form(s) of DC may exist. We have studied a 6-year-old black girl with the characteristic triad of nail dystrophy, cutaneous and mucosal pigmentary changes, and bone marrow failure. Severe microcephaly, mental retardation, cerebellar hypoplasia, and purple discoloration of the tongue were other manifestations not usually seen in DC. Comparison of our patient's phenotype with that of 5 other sporadic and 10 familial cases of DC in females showed that the autosomal and X-linked phenotypes are not distinguishable in the absence of a suggestive pedigree pattern. Additional cases of DC need to be studied to better elucidate the apparent causal heterogeneity in this syndrome.