Πέμπτη 14 Απριλίου 2016

Mutations in PRPS1 causing syndromic or nonsyndromic hearing impairment: intrafamilial phenotypic variation complicates genetic counseling.

http:--http://ift.tt/1PAyOTB Related Articles

Mutations in PRPS1 causing syndromic or nonsyndromic hearing impairment: intrafamilial phenotypic variation complicates genetic counseling.

Pediatr Res. 2015 Jul;78(1):97-102

Authors: Gandía M, Fernández-Toral J, Solanellas J, Domínguez-Ruiz M, Gómez-Rosas E, Del Castillo FJ, Villamar M, Moreno-Pelayo MA, Del Castillo I

Abstract
BACKGROUND: PRPS1 encodes isoform I of phosphoribosylpyrophosphate synthetase (PRS-I), a key enzyme in nucleotide biosynthesis. Different missense mutations in PRPS1 cause a variety of disorders that include PRS-I superactivity, nonsyndromic sensorineural hearing impairment, Charcot-Marie-Tooth disease, and Arts syndrome. It has been proposed that each mutation would result in a specific phenotype, depending on its effects on the structure and function of the enzyme.
METHODS: Thirteen Spanish unrelated families segregating X-linked hearing impairment were screened for PRPS1 mutations by Sanger sequencing. In two positive pedigrees, segregation of mutations was studied, and clinical data from affected subjects were compared.
RESULTS: We report two novel missense mutations in PRPS1, p.Ile275Thr and p.Gly306Glu, which were found in the propositi of two unrelated Spanish families, both subjects presenting with nonsyndromic hearing impairment. Further investigation revealed syndromic features in other hemizygous carriers from one of the pedigrees. Sequencing of genes that are functionally related to PRPS1 did not reveal any candidate variant that might act as a phenotype modifier.
CONCLUSION: This case of intrafamilial phenotypic variation associated with a single PRPS1 mutation complicates the genotype-phenotype correlations, which makes genetic counseling of mutation carriers difficult because of the wide spectrum of severity of the associated disorders.

PMID: 25785835 [PubMed - indexed for MEDLINE]



from #Audiology via xlomafota13 on Inoreader http://ift.tt/1Na7ThX
via IFTTT

Δεν υπάρχουν σχόλια:

Δημοσίευση σχολίου