title: Novel variants of RPGR in X-linked retinitis pigmentosa families and genotype-phenotype correlation.
abstract: OBJECTIVE
  To identify novel mutations in the retinitis pigmentosa GTPase regulator (RPGR) gene and retinitis pigmentosa 2 (RP2) gene underlying X-linked retinitis pigmentosa (XLRP) and assess genotype-phenotype correlations.
  
  
  METHODS
  The patient cohort, consisting of 13 individuals from 3 unrelated XLRP families, underwent comprehensive ophthalmologic examination. The open reading frames of RPGR and RP2 were analyzed with Sanger sequencing in each patient. The identified genetic variants were defined as mutations or polymorphisms on the basis of their pathological effect.
  
  
  RESULTS
  We found 3 genetic variants: a novel mutation c.1591G>T in exon 14 and a novel polymorphism c.1105C>T in exon 10, resulting in p.Glu531* and p.Arg369Cys of RPGR gene, respectively, and one already known mutation c.413A>G in exon 2, resulting in a p.Glu138Gly of RP2 gene. Considering our XLRP probands, RPGR-related phenotypic damages were similar and less severe than those of the patient with the RP2 mutation. On the other hand, the female carriers of XLRP variants showed different RPGR-related consequences, ranging from rods hypofunctionality in c.1591G>T nonsense heterozygosity to no retinal changes in c.1105C>T polymorphic heterozygosity.
  
  
  CONCLUSIONS
  These findings broaden the spectrum of RPGR mutations and phenotypic variability of the disease, which will be useful for genetic consultation and diagnosis in the future.
authors:  Department of Biomedical and Specialty Surgical Sciences, University of Ferrara, Ferrara - Italy.
authors: Francesco
authors: F
authors: Parmeggiani
authors:  Veneto Eye Bank Foundation, Mestre (Venice) - Italy.
authors: Vanessa
authors: V
authors: Barbaro
authors:  Department of Molecular Medicine, University of Padua, Padua - Italy.
authors: Angelo
authors: A
authors: Migliorati
authors:  Department of Molecular Medicine, University of Padua, Padua - Italy.
authors: Paolo
authors: P
authors: Raffa
authors:  Department of Molecular Medicine, University of Padua, Padua - Italy.
authors: Patrizia
authors: P
authors: Nespeca
authors:  Department of Biomedical and Specialty Surgical Sciences, University of Ferrara, Ferrara - Italy.| Center for Retinitis Pigmentosa of Veneto Region, ULSS 15 Alta Padovana, Camposampiero (Padua) - Italy.
authors: Katia
authors: K
authors: De Nadai
authors:  Department of Molecular Medicine, University of Padua, Padua - Italy.
authors: Claudia
authors: C
authors: Del Vecchio
authors:  Department of Molecular Medicine, University of Padua, Padua - Italy.
authors: Giorgio
authors: G
authors: Palù
authors:  Department of Molecular Medicine, University of Padua, Padua - Italy.
authors: Cristina
authors: C
authors: Parolin
authors:  Department of Molecular Medicine, University of Padua, Padua - Italy.
authors: Enzo
authors: E
authors: Di Iorio
mesh_terms: D000328:Adult; D004252:DNA Mutational Analysis; D005091:Exons; D005136:Eye Proteins / Q000235:genetics*; D005260:Female; D019204:GTP-Binding Proteins; D056726:Genetic Association Studies; D040181:Genetic Diseases, X-Linked; D005838:Genotype; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins / Q000235:genetics*; D008297:Male; D008565:Membrane Proteins / Q000235:genetics*; D008869:Microtubule-Associated Proteins; D008875:Middle Aged; D009154:Mutation; D010375:Pedigree; D010641:Phenotype; D012174:Retinitis Pigmentosa / Q000235:genetics*; D014792:Visual Acuity; D055815:Young Adult
chemical_list: D005136:Eye Proteins; D047908:Intracellular Signaling Peptides and Proteins; D008565:Membrane Proteins; D008869:Microtubule-Associated Proteins; C120042:RP1 protein, human; C072178:RP2 protein, human; D019204:GTP-Binding Proteins