Does DKC1 Mutation Suffice to Define the Phenotype Severity of Hoyeraal-Hreidarsson Syndrome?

Elvis Terci Valera, María Sol Brassesco, Sabrine Teixeira Ferraz, Pérsio Roxo Jr.², Barbara Lemos-Santana, Tom Vulliamy, Rodrigo Tocantins Calado, Carlos Alberto Scrideli, Luiz Gonzaga Tone

Centre for Paediatrics, Blizard Institute, Barts and The London School of Medicine and Dentistry, London, UK.
Department of Internal Medicine, Faculty of Medicine of Ribeir?o Preto, University of S?o Paulo, Ribeir?o Preto, Brazil.
Division of Pediatric Oncology, Department of Pediatrics, Bairro Monte Alegre, Ribeir?o Preto, Brazil.
Faculty of Medicine of Ribeira?o Preto, University of Sa?o Paulo, Ribeira?o Preto, Brazil.

DOI: 10.4236/ojbd.2013.31012                

Abstract

Both dyskeratosis congenita (DC) and Hoyeraal-Hreidarsson Syndrome (HHS) are rare inherited bone marrow failure conditions. HHS is considered to be a variant of DC in which neurological deficits and immunodeficiencies are also present. We describe a very interesting familial cluster where an invariant point mutation of DKC1 located in the exon 11 is observed in the carrier mother and in two decedent males. The older child developed the classical phenotype of HHS at a very early age. The second affected child remains poorly symptomatic, with only mild haematological changes. Telomere shortening, with different severity, is also present in both cases. This paper discusses the clinical spectrum of inherited BM failure syndromes from the perspective different clinical presentation within a family with a DKC1 mutation.

Keywords

DKC1 Mutation; Dyskeratosis Congenital; Hoyeraal-Hreidarsson Syndrome; Bone Marrow Failure

Conflicts of Interest

The authors declare no conflicts of interest.

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