Clericuzio-Type Poikiloderma With Neutropenia Syndrome in Three Sibs With Mutations in the C16orf57 Gene: Delineation of the Phenotype

Dipartimento di Pediatria, Università Magna Graecia, Ospedale Civile A. Pugliese, Catanzaro, Italy.
American Journal of Medical Genetics Part A (Impact Factor: 2.16). 10/2010; 152A(10):2588-94. DOI: 10.1002/ajmg.a.33600
Source: PubMed


We report on three sibs who have autosomal recessive Clericuzio-type poikiloderma neutropenia (PN) syndrome. Recently, this consanguineous family was reported and shown to be informative in identifying the C16orf57 gene as the causative gene for this syndrome. Here we present the clinical data in detail. PN is a distinct and recognizable entity belonging to the group of poikiloderma syndromes among which Rothmund-Thomson is perhaps the best described and understood. PN is characterized by cutaneous poikiloderma, hyperkeratotic nails, generalized hyperkeratosis on palms and soles, neutropenia, short stature, and recurrent pulmonary infections. In order to delineate the phenotype of this rare genodermatosis, the clinical presentation together with the molecular investigations in our patients are reported and compared to those from the literature.

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    • "Indeed, apart from our patients #17a and the infant #25, all herein described PN patients display overt skeletal signs including zygodactyly between the second and third digit (#26), multiple bone fractures (#11), intermediate osteopetrosis (#21) or X-ray detectable skeletal findings (#16) (Table 1). A relationship may be envisaged between zygodactyly and the swan neck hand hyperflexibility noticed in a few described patients [3,5,33]. More generally delayed bone maturation has been recorded [32] in the girl subsequently confirmed to carry two distinct C16orf57 mutations [6], and diffuse osteosclerosis has been underlined by Porter [26] in the patient found to harbour C16orf57 mutations [10]. "
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