@article {489, title = {Exome sequencing reveals novel and recurrent mutations with clinical significance in inherited retinal dystrophies.}, journal = {PLoS One}, volume = {9}, year = {2014}, month = {2014}, pages = {e116176}, abstract = {

This study aimed to identify the underlying molecular genetic cause in four Spanish families clinically diagnosed of Retinitis Pigmentosa (RP), comprising one autosomal dominant RP (adRP), two autosomal recessive RP (arRP) and one with two possible modes of inheritance: arRP or X-Linked RP (XLRP). We performed whole exome sequencing (WES) using NimbleGen SeqCap EZ Exome V3 sample preparation kit and SOLID 5500xl platform. All variants passing filter criteria were validated by Sanger sequencing to confirm familial segregation and the absence in local control population. This strategy allowed the detection of: (i) one novel heterozygous splice-site deletion in RHO, c.937-2_944del, (ii) one rare homozygous mutation in C2orf71, c.1795T>C; p.Cys599Arg, not previously associated with the disease, (iii) two heterozygous null mutations in ABCA4, c.2041C>T; p.R681* and c.6088C>T; p.R2030*, and (iv) one mutation, c.2405-2406delAG; p.Glu802Glyfs*31 in the ORF15 of RPGR. The molecular findings for RHO and C2orf71 confirmed the initial diagnosis of adRP and arRP, respectively, while patients with the two ABCA4 mutations, both previously associated with Stargardt disease, presented symptoms of RP with early macular involvement. Finally, the X-Linked inheritance was confirmed for the family with the RPGR mutation. This latter finding allowed the inclusion of carrier sisters in our preimplantational genetic diagnosis program.

}, keywords = {Adolescent, Adult, Amino Acid Sequence, Base Sequence, Child, Chromosome Segregation, DNA Mutational Analysis, Exome, Family, Female, Humans, Inheritance Patterns, Male, Middle Aged, Molecular Sequence Data, mutation, Pedigree, Retinal Dystrophies, Rhodopsin}, issn = {1932-6203}, doi = {10.1371/journal.pone.0116176}, author = {Gonz{\'a}lez-del Pozo, Mar{\'\i}a and M{\'e}ndez-Vidal, Cristina and Bravo-Gil, Nereida and Vela-Boza, Alicia and Dopazo, Joaquin and Borrego, Salud and Anti{\v n}olo, Guillermo} } @article {490, title = {Novel RP1 mutations and a recurrent BBS1 variant explain the co-existence of two distinct retinal phenotypes in the same pedigree.}, journal = {BMC Genet}, volume = {15}, year = {2014}, month = {2014 Dec 14}, pages = {143}, abstract = {

BACKGROUND: 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).

RESULTS: 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.

CONCLUSIONS: 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.

}, keywords = {Bardet-Biedl Syndrome, Base Sequence, Case-Control Studies, DNA Mutational Analysis, Eye Proteins, Genes, Recessive, Genetic Association Studies, Humans, Microsatellite Repeats, Microtubule-Associated Proteins, Mutation, Missense, Pedigree, Phenotype, Retina, Retinitis pigmentosa}, issn = {1471-2156}, doi = {10.1186/s12863-014-0143-2}, author = {M{\'e}ndez-Vidal, Cristina and Bravo-Gil, Nereida and Gonz{\'a}lez-del Pozo, Mar{\'\i}a and Vela-Boza, Alicia and Dopazo, Joaquin and Borrego, Salud and Anti{\v n}olo, Guillermo} } @article {575, title = {Mutation spectrum of EYS in Spanish patients with autosomal recessive retinitis pigmentosa.}, journal = {Hum Mutat}, volume = {31}, year = {2010}, month = {2010 Nov}, pages = {E1772-800}, abstract = {

Retinitis pigmentosa (RP) is a heterogeneous group of inherited retinal dystrophies characterised ultimately by the loss of photoreceptor cells. We have recently identified a new gene(EYS) encoding an ortholog of Drosophila space maker (spam) as a commonly mutated gene in autosomal recessive RP. In the present study, we report the identification of 73 sequence variations in EYS, of which 28 are novel. Of these, 42.9\% (12/28) are very likely pathogenic, 17.9\% (5/28)are possibly pathogenic, whereas 39.3\% (11/28) are SNPs. In addition, we have detected 3 pathogenic changes previously reported in other populations. We are also presenting the characterisation of EYS homologues in different species, and a detailed analysis of the EYS domains, with the identification of an interesting novel feature: a putative coiled-coil domain.Majority of the mutations in the arRP patients have been found within the domain structures of EYS. The minimum observed prevalence of distinct EYS mutations in our group of patients is of 15.9\% (15/94), confirming a major involvement of EYS in the pathogenesis of arRP in the Spanish population. Along with the detection of three recurrent mutations in Caucasian population, our hypothesis of EYS being the first prevalent gene in arRP has been reinforced in the present study.

}, keywords = {Amino Acid Sequence, Animals, Case-Control Studies, DNA Mutational Analysis, Drosophila Proteins, Evolution, Molecular, Eye Proteins, Female, Genes, Recessive, Genetic Variation, Humans, Male, Molecular Sequence Data, mutation, Pedigree, Polymorphism, Single Nucleotide, Protein Structure, Tertiary, Retinitis pigmentosa, Spain, Structural Homology, Protein}, issn = {1098-1004}, doi = {10.1002/humu.21334}, author = {Barrag{\'a}n, Isabel and Borrego, Salud and Pieras, Juan Ignacio and Gonz{\'a}lez-del Pozo, Mar{\'\i}a and Santoyo, Javier and Ayuso, Carmen and Baiget, Montserrat and Mill{\'a}n, Jos{\'e} M and Mena, Marcela and Abd El-Aziz, Mai M and Audo, Isabelle and Zeitz, Christina and Littink, Karin W and Dopazo, Joaquin and Bhattacharya, Shomi S and Anti{\v n}olo, Guillermo} }