Un nuevo paciente con deleción 10p y revisión de la literatura. Estudio de la correlación genotipo-fenotipo

Abstract

Since the first report by Elliott et al., in 1970, of a patient with partial deletion of the short arm of chromosome 10 (10p), at least 67 further cases have been reported, of which 44 were pure de novo deletions. Two syndromes have been associated with deletions of 10p: DiGeorge 2 syndrome (DGS2) and HDR (Hypothyroidism, sensorineural Deafness and Renal disease). DGS2 (so-named due to its similitude to DiGeorge syndrome) is characterised by congenital heart defects, dysmorphism, hypoplastic thymus with T-cell deficiency, and hypoparathyroidism with hypocalcemia. In 1984, Herve et al. published the first case that associated a deletion of 10p with a clinical picture of DiGeorge, and a critical region, of approximately 1 Mb, in 10p13-p14 was delineated in 1998 by Schuffenhauer et al. On the other hand, HDR syndrome was first described in 1977 by Barakat et al., and in 1997 the syndrome was associated with a deletion of 10p. The observation that such deletions in patients with HDR were outside the DGS2 critical region led to the discovery of a causal gene, GATA3 located in 10p14, which has an important role in embryonic development of the kidney, parathyroids and auditory system. Here we present a patient with a 10p deletion that includes both the DGS2 critical region and GATA3 gene. The propositus’ clinical picture includes facial dysmorphism, unilateral ptosis, unilateral renal agenesis and hypoacusia. We carried out a revision of the literature, as well as a comparative analysis of the clinical characteristics and the cytoband affected, with the aim of correlating the main manifestations with the region of 10p deleted. The results have shown an overlap of clinical features as well as a great variability of manifestations among patients with different 10p deletions. No correlation could be established between the deleted genes and clinical manifestations, thus suggesting the involvement of more complex molecular mechanisms.