02531nas a2200361   4500008004100000022001400041245008000055210006900135260001300204300001300217490000800230520137100238653001801609653004901627653003401676653001701710653001101727653002801738653002301766653001301789653002501802653002701827653001001854100003301864700002301897700002801920700003301948700002201981700002002003700001902023700002502042856010202067       2015                        eng d  a1552-483300aRe-evaluation casts doubt on the pathogenicity of homozygous USH2A p.C759F.0 aReevaluation casts doubt on the pathogenicity of homozygous USH2  c2015 Jul  a1597-6000 v1673 a<p>Mutations in USH2A are a common cause of Retinitis Pigmentosa (RP). Among the most frequently reported USH2A variants, c.2276G>T (p.C759F) has been found in both affected and healthy individuals. The pathogenicity of this variant remains controversial since it was detected in homozygosity in two healthy siblings of a Spanish family (S23), eleven years ago. The fact that these individuals remain asymptomatic today, prompted us to study the presence of other pathogenic variants in this family using targeted resequencing of 26 retinal genes in one of the affected individuals. This approach allowed us to identify one novel pathogenic homozygous mutation in exon 13 of PDE6B (c.1678C>T; p.R560C). This variant cosegregated with the disease and was absent in 200 control individuals. Remarkably, the identified variant in PDE6B corresponds to the mutation responsible of the retinal degeneration in the naturally occurring rd10 mutant mice. To our knowledge, this is the first report of the identification of the rd10 mice mutation in a RP family. These findings, together with a review of the literature, support the hypothesis that homozygous p.C759F mutations are not pathogenic and led us to exclude the implication of p.C759F in the RP of family S23. Our results indicate the need of re-evaluating all families genetically diagnosed with this mutation.</p>10aBase Sequence10aCyclic Nucleotide Phosphodiesterases, Type 610aExtracellular Matrix Proteins10aGene Library10aHumans10aMolecular Sequence Data10aMutation, Missense10aPedigree10aRetinitis pigmentosa10aSequence Analysis, DNA10aSpain1 aDel Pozo, María, González-1 aBravo-Gil, Nereida1 aMéndez-Vidal, Cristina1 aMontero-de-Espinosa, Ignacio1 aMillán, José, M1 aDopazo, Joaquin1 aBorrego, Salud1 aAntiňolo, Guillermo  uhttp://clinbioinfosspa.es/content/re-evaluation-casts-doubt-pathogenicity-homozygous-ush2a-pc759f03760nas a2200397   4500008004100000022001400041245013500055210006900190260001600259300000800275490000700283520244800290653002602738653001802764653002502782653002802807653001702835653002102852653003202873653001102905653002702916653003602943653002302979653001303002653001403015653001103029653002503040100002803065700002303093700003303116700002203149700002003171700001903191700002503210856012703235       2014                        eng d  a1471-215600aNovel RP1 mutations and a recurrent BBS1 variant explain the co-existence of two distinct retinal phenotypes in the same pedigree.0 aNovel RP1 mutations and a recurrent BBS1 variant explain the coe  c2014 Dec 14  a1430 v153 a<p><b>BACKGROUND: </b>Molecular diagnosis of Inherited Retinal Dystrophies (IRD) has long been challenging due to the extensive clinical and genetic heterogeneity present in this group of disorders. Here, we describe the clinical application of an integrated next-generation sequencing approach to determine the underlying genetic defects in a Spanish family with a provisional clinical diagnosis of autosomal recessive Retinitis Pigmentosa (arRP).</p><p><b>RESULTS: </b>Exome sequencing of the index patient resulted in the identification of the homozygous BBS1 p.M390R mutation. Sanger sequencing of additional members of the family showed lack of co-segregation of the p.M390R variant in some individuals. Clinical reanalysis indicated co-ocurrence of two different phenotypes in the same family: Bardet-Biedl syndrome in the individual harboring the BBS1 mutation and non-syndromic arRP in extended family members. To identify possible causative mutations underlying arRP, we conducted disease-targeted gene sequencing using a panel of 26 IRD genes. The in-house custom panel was validated using 18 DNA samples known to harbor mutations in relevant genes. All variants were redetected, indicating a high mutation detection rate. This approach allowed the identification of two novel heterozygous null mutations in RP1 (c.4582_4585delATCA; p.I1528Vfs*10 and c.5962dupA; p.I1988Nfs*3) which co-segregated with the disease in arRP patients. Additionally, a mutational screening in 96 patients of our cohort with genetically unresolved IRD revealed the presence of the c.5962dupA mutation in one unrelated family.</p><p><b>CONCLUSIONS: </b>The combination of molecular findings for RP1 and BBS1 genes through exome and gene panel sequencing enabled us to explain the co-existence of two different retinal phenotypes in a family. The identification of two novel variants in RP1 suggests that the use of panels containing the prevalent genes of a particular population, together with an optimized data analysis pipeline, is an efficient and cost-effective approach that can be reliably implemented into the routine diagnostic process of diverse inherited retinal disorders. Moreover, the identification of these novel variants in two unrelated families supports the relatively high prevalence of RP1 mutations in Spanish population and the role of private mutations for commonly mutated genes, while extending the mutational spectrum of RP1.</p>10aBardet-Biedl Syndrome10aBase Sequence10aCase-Control Studies10aDNA Mutational Analysis10aEye Proteins10aGenes, Recessive10aGenetic Association Studies10aHumans10aMicrosatellite Repeats10aMicrotubule-Associated Proteins10aMutation, Missense10aPedigree10aPhenotype10aRetina10aRetinitis pigmentosa1 aMéndez-Vidal, Cristina1 aBravo-Gil, Nereida1 adel Pozo, María, González-1 aVela-Boza, Alicia1 aDopazo, Joaquin1 aBorrego, Salud1 aAntiňolo, Guillermo  uhttp://clinbioinfosspa.es/content/novel-rp1-mutations-and-recurrent-bbs1-variant-explain-co-existence-two-distinct-retinal