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The combined analysis of haplotype panels with phenotype clinical cohorts is a common approach to explore the genetic architecture of human diseases. However, genetic studies are mainly based on single nucleotide variants (SNVs) and small insertions and deletions (indels). Here, we contribute to fill this gap by generating a dense haplotype map focused on the identification, characterization, and phasing of structural variants (SVs). By integrating multiple variant identification methods and Logistic Regression Models (LRMs), we present a catalogue of 35 431 441 variants, including 89 178 SVs (≥50 bp), 30 325 064 SNVs and 5 017 199 indels, across 785 Illumina high coverage (30x) whole-genomes from the Iberian GCAT Cohort, containing a median of 3.52M SNVs, 606 336 indels and 6393 SVs per individual. The haplotype panel is able to impute up to 14 360 728 SNVs/indels and 23 179 SVs, showing a 2.7-fold increase for SVs compared with available genetic variation panels. The value of this panel for SVs analysis is shown through an imputed rare Alu element located in a new locus associated with Mononeuritis of lower limb, a rare neuromuscular disease. This study represents the first deep characterization of genetic variation within the Iberian population and the first operational haplotype panel to systematically include the SVs into genome-wide genetic studies. GCAT|Genomes for Life, a cohort study of the Genomes of Catalonia, Fundació Institut Germans Trias i Pujol (IGTP); IGTP is part of the CERCA Program/Generalitat de Catalunya; GCAT is supported by Acción de Dinamización del ISCIII-MINECO; Ministry of Health of the Generalitat of Catalunya [ADE 10/00026]; Agència de Gestió d’Ajuts Universitaris i de Recerca (AGAUR) [2017-SGR 529]; B.C. is supported by national grants [PI18/01512]; X.F. is supported by VEIS project [001-P-001647] (co-funded by European Regional Development Fund (ERDF), ‘A way to build Europe’); a full list of the investigators who contributed to the generation of the GCAT data is available from www.genomesforlife.com/; Severo Ochoa Program, awarded by the Spanish Government [SEV-2011-00067 and SEV2015-0493]; Spanish Ministry of Science [TIN2015-65316-P]; Innovation and by the Generalitat de Catalunya [2014-SGR-1051 to D.T.]; Agencia Estatal de Investigación (AEI, Spain) [BFU2016-77244-R and PID2019-107836RB-I00]; European Regional Development Fund (FEDER, EU) (to M.C.); Spanish Ministry of Science and Innovation [FPI BES-2016-0077344 to J.V.M.]; C.S. received funding from the European Union's Horizon 2020 research and innovation program under the Marie Skłodowska-Curie grant agreement [H2020-MSCA-COFUND-2016-754433]; this study made use of data generated by the UK10K Consortium from UK10K COHORT IMPUTATION [EGAS00001000713]; formal agreement with the Barcelona Supercomputing Center (BSC); this study made use of data generated by the Genome of the Netherlands’ project, which is funded by the Netherlands Organization for Scientific Research [184021007], allowing us to use the GoNL reference panel containing SVs, upon request (GoNL Data Access request 2019203); this study also used data generated by the Haplotype Reference Consortium (HRC) accessed through the European Genome-phenome Archive with the accession numbers EGAD00001002729; formal agreement of the Barcelona Supercomputing Center (BSC) with WTSI; this study made use of data generated by the 1000 Genomes (1000G), accessed through the FTP portal (http://ftp.1000genomes.ebi.ac.uk/vol1/ftp/release/20130502/); this study used the GeneHancer-for-AnnotSV dump for GeneCards Suite Version 4.14, through a formal agreement between the BSC and the Weizmann Institute of Science. Funding for open access charge: GCAT|Genomes for Life, a cohort study of the Genomes of Catalonia, Fundació Institut Germans Trias i Pujol (IGTP); IGTP is part of the CERCA Program/Generalitat de Catalunya; GCAT is supported by Acción de Dinamización del ISCIII-MINECO; Ministry of Health of the Generalitat of Catalunya [ADE 10/00026]; Agència de Gestió d’Ajuts Universitaris i de Recerca (AGAUR) [2017-SGR 529]; B.C. is supported by national grants [PI18/01512]; X.F. is supported by VEIS project [001-P-001647] (co-funded by European Regional Development Fund (ERDF), ‘A way to build Europe’); a full list of the investigators who contributed to the generation of the GCAT data is available from www.genomesforlife.com/; Severo Ochoa Program, awarded by the Spanish Government [SEV-2011-00067 and SEV2015-0493]; Spanish Ministry of Science [TIN2015-65316-P]; Innovation and by the Generalitat de Catalunya [2014-SGR-1051 to D.T.]; [Agencia Estatal de Investigación (AEI, Spain) [BFU2016-77244-R and PID2019-107836RB-I00]; European Regional Development Fund (FEDER, EU) (to M.C.); Spanish Ministry of Science and Innovation [FPI BES-2016-0077344 to J.V.M.]; C.S. received funding from the European Union's Horizon 2020 research and innovation program under the Marie Skłodowska-Curie grant agreement [H2020-MSCA-COFUND-2016-754433]; this study made use of data generated by the UK10K Consortium from UK10K COHORT IMPUTATION [EGAS00001000713]; formal agreement with the Barcelona Supercomputing Center (BSC); this study made use of data generated by the Genome of the Netherlands’ project, which is funded by the Netherlands Organization for Scientific Research [184021007], allowing us to use the GoNL reference panel containing SVs, upon request (GoNL Data Access request 2019203); this study also used data generated by the Haplotype Reference Consortium (HRC) accessed through the European Genome-phenome Archive with the accession numbers EGAD00001002729; formal agreement of the Barcelona Supercomputing Center (BSC) with WTSI; this study made use of data generated by the 1000 Genomes (1000G), accessed through the FTP portal (http://ftp.1000genomes.ebi.ac.uk/vol1/ftp/release/20130502/); this study used the GeneHancer-for-AnnotSV dump for GeneCards Suite Version 4.14, through a formal agreement between the BSC and The Weizmann Institute of Science. "Article signat per 21 autors/es: Jordi Valls-Margarit, Iván Galván-Femenía, Daniel Matías-Sánchez, Natalia Blay, Montserrat Puiggròs, Anna Carreras, Cecilia Salvoro, Beatriz Cortés, Ramon Amela, Xavier Farre, Jon Lerga-Jaso, Marta Puig, Jose Francisco Sánchez-Herrero, Victor Moreno, Manuel Perucho, Lauro Sumoy, Lluís Armengol, Olivier Delaneau, Mario Cáceres, Rafael de Cid, David Torrents"

PRMT7 encodes for an arginine methyltransferase that methylates arginine residues on various protein substrates and has been shown to play a role in various developmental processes. Mutations in PRMT7 have been recently shown to be implicated in a phenotype with intellectual disability, short stature and brachydactyly, and considered to be a phenocopy of pseudohypoparathyroidism. We report a patient with short stature, psychomotor delay, hearing loss and brachydactyly, for whom whole exome sequencing detected two mutations in PRMT7 and parental segregation studies detected biallelic mutation inheritance. Few patients with biallelic PRMT7 mutations have been reported so far in the literature. We report a new patient and review all reported cases to date to delineate the clinical manifestations that may help in diagnosis this disorder, known as Short Stature, Brachydactyly, Intellectual Developmental Disability, and Seizures syndrome, allowing appropriate management and genetic counselling.

The combined analysis of haplotype panels with phenotype clinical cohorts is a common approach to explore the genetic architecture of human diseases. However, genetic studies are mainly based on single nucleotide variants (SNVs) and small insertions and deletions (indels). Here, we contribute to fill this gap by generating a dense haplotype map focused on the identification, characterization and phasing of structural variants (SVs). By integrating multiple variant identification methods and Logistic Regression models, we present a catalogue of 35,431,441 variants, including 89,178 SVs (≥50bp), 30,325,064 SNVs and 5,017,199 indels, across 785 Illumina high coverage (30X) whole-genomes from the Iberian GCAT Cohort, containing 3.52M SNVs, 606,336 indels and 6,393 SVs in median per individual. The haplotype panel is able to impute up to 14,360,728 SNVs/indels and 23,179 SVs, showing a 2.7-fold increase for SVs compared with available genetic variation panels. The value of this panel for SVs analysis is shown through an imputed rare Alu element located in a new locus associated with mononeuritis of lower limb, a rare neuromuscular disease. This study represents the first deep characterization of genetic variation within the Iberian population and the first operational haplotype panel to systematically include the SVs into genome-wide genetic studies.

Background There is increasing evidence of the importance of copy number variants (CNV) in genetic diversity among individuals and populations, as well as in some common genetic diseases. We previously characterized a common 32-kb insertion/deletion variant of the PSORS4 locus at chromosome 1q21 that harbours the LCE3C and LCE3B genes. This variant allele (LCE3C_LCE3B-del) is common in patients with psoriasis and other autoimmune disorders from certain ethnic groups. Results Using array-CGH (Agilent 244 K) in samples from the HapMap and Human Genome Diversity Panel (HGDP) collections, we identified 54 regions showing population differences in comparison to Africans. We provided here a comprehensive population-genetic analysis of one of these regions, which involves the 32-kb deletion of the PSORS4 locus. By a PCR-based genotyping assay we characterised the profiles of the LCE3C_LCE3B-del and the linkage disequilibrium (LD) pattern between the variant allele and the tag SNP rs4112788. Our results show that most populations tend to have a higher frequency of the deleted allele than Sub-Saharan Africans. Furthermore, we found strong LD between rs4112788G and LCE3C_LCE3B-del in most non-African populations (r2 >0.8), in contrast to the low concordance between loci (r2 Conclusions These results are another example of population variability in terms of biomedical interesting CNV. The frequency distribution of the LCE3C_LCE3B-del allele and the LD pattern across populations suggest that the differences between ethnic groups might not be due to natural selection, but the consequence of genetic drift caused by the strong bottleneck that occurred during “out of Africa” expansion.

A genetic analysis of unexplained mild-moderate intellectual disability and co-morbid psychiatric or behavioural disorders is not systematically conducted in adults. A cohort of 100 adult patients affected by both phenotypes were analysed in order to identify the presence of copy number variants (CNVs) responsible for their condition identifying a yield of 12.8% of pathogenic CNVs (19% when including clinically recognizable microdeletion syndromes). Moreover, there is a detailed clinical description of an additional 11% of the patients harbouring possible pathogenic CNVs—including a 7q31 deletion (IMMP2L) in two unrelated patients and duplications in 3q29, 9p24.2p24.1 and 15q14q15.1—providing new evidence of its contribution to the phenotype. This study adds further proof of including chromosomal microarray analysis (CMA) as a mandatory test to improve the diagnosis in the adult patients in psychiatric services. Electronic supplementary material The online version of this article (10.1007/s10519-018-9902-6) contains supplementary material, which is available to authorized users.

Resumen El presente estudio describe la implementacion de un test de cribado de portadores de enfermedades geneticas autosomicas recesivas y enfermedades ligadas al cromosoma X en un programa de donacion de ovocitos (donantes de ovocitos y parejas masculinas de las receptoras). El test empleado basado en tecnologia Next-Generation Sequencing (NGS), cubria 200 genes (68 mediante analisis completo de secuencia codificante y 132 por estrategia dirigida de analisis) asociados a 314 enfermedades (277 enfermedades autosomicas recesivas y 22 ligadas al cromosoma X). El resultado obtenido tras 2,5 anos mostro un alto grado de aceptacion (implementacion > 80%). Se identificaron un 56,4% de individuos (761/1.350) portadores de al menos una mutacion patogenica. Asimismo se identifico que el 1,9% de las candidatas a donantes eran portadoras de una enfermedad ligada al cromosoma X por lo que se excluyeron del programa de Donacion de Ovocitos. La carga mutacional media fue de 0,84 mutaciones por muestra. Se identificaron un 3,4% de preasignaciones donante-receptor con alto riesgo reproductivo para alguna enfermedad genetica recesiva (fibrosis quistica, hiperplasia suprarrenal congenita, sordera congenita no-sindromica, alfa-talasemia, fiebre mediterranea familiar, enfermedad de Niemann-Pick, dishormonogenesis tiroidea tipo 6 e hipoplasia de cartilago-pelo). La asignacion definitiva se realizo teniendo en cuenta los resultados de los estudios geneticos. El estado de portador heterocigoto para una enfermedad autosomica recesiva no fue motivo de exclusion del programa de Donacion de Ovocitos, pero implico la seleccion de una receptora cuya pareja masculina no fuera portadora de la misma enfermedad. El asesoramiento genetico de donantes y receptores en las diferentes etapas del proceso clinico de la donacion de ovocitos fue esencial para disminuir la ansiedad, conseguir una buena comprension de los resultados y poder otorgar las recomendaciones pertinentes sobre el riesgo reproductivo propio o de sus familiares, cuando fue necesario.

[Background]: Distal motor neuropathies with a genetic origin have a heterogeneous clinical presentation with overlapping features affecting distal nerves and including spinal muscular atrophies and amyotrophic lateral sclerosis. This indicates that their genetic background is heterogeneous., [Patient and methods]: In this work, we have identified and characterized the genetic and molecular base of a patient with a distal sensorimotor neuropathy of unknown origin. For this study, we performed whole‐exome sequencing, molecular modelling, cloning and expression of mutant gene, and biochemical and cell biology analysis of the mutant protein., [Results]: A novel homozygous recessive mutation in the human VRK1 gene, coding for a chromatin kinase, causing a substitution (c.637T > C; p.Tyr213His) in exon 8, was detected in a patient presenting since childhood a progressive distal sensorimotor neuropathy and spinal muscular atrophy syndrome, with normal intellectual development. Molecular modelling predicted this mutant VRK1 has altered the kinase activation loop by disrupting its interaction with the C‐terminal regulatory region. The p.Y213H mutant protein has a reduced kinase activity with different substrates, including histones H3 and H2AX, proteins involved in DNA damage responses, such as p53 and 53BP1, and coilin, the scaffold for Cajal bodies. The mutant VRK1(Y213H) protein is unable to rescue the formation of Cajal bodies assembled on coilin, in the absence of wild‐type VRK1., [Conclusion]: The VRK1(Y213H) mutant protein alters the activation loop, impairs the kinase activity of VRK1 causing a functional insufficiency that impairs the formation of Cajal bodies assembled on coilin, a protein that regulates SMN1 and Cajal body formation., E. M‐D., and P. M‐G. were supported by Junta de Castilla y León‐Fondo Social Europeo (ESF), and Ministerio de Educación‐FPU predoctoral (FPU16/01883) fellowships, respectively. This work was funded by grants from Ministerio de Ciencia, Innovación y Universidades‐Agencia Estatal de Investigación (SAF2016‐75744‐R, RED2018‐102801‐T) and Consejería de Educación‐Junta de Castilla y León‐ERDF (UIC‐258) to P.A.L. Ministerio de Ciencia, Innovación y Universidades‐Agencia Estatal de Investigación (RTC‐2017‐6494‐1 and RTI2018‐094434‐B‐I00) and European Commission project "CONNECT‐JPIAMR” Virtual Research Institute to P.G‐P. The Instituto de Biología Molecular y Celular del Cáncer is cofunded by Junta de Castilla y León‐European Regional Development Fund (CLC–2017–01).

Early-onset Alzheimer’s disease (EOAD) and frontotemporal dementia (FTD) have a high proportion of genetically determined cases. Next-generation sequencing technologies have triggered the discovery of new mutations and genetic variants in dementia-causal genes. We performed whole-exome sequencing and selective analysis of known genes causative of EOAD and FTD in a well-characterized Spanish cohort of 103 patients (60 EOAD, 43 FTD) to find genetic variants associated to patients’ phenotype. In EOAD patients, a new likely pathogenic variant in PSEN1 gene (p.G378R) was found. In FTD patients, 2 likely pathogenic variants were found, one in MAPT gene (p.P397S) and one in VCP gene (p.R159H). In our series, 2% of early-onset dementia without criteria for clinical genetic testing according to current guidelines presented a likely pathogenic mutation. We have also detected 13 additional variants of uncertain significance in causal genes, as well as rare variants in risk genes for dementia (ABCA7, SORL1, SQSTM1, and TREM2). Next-generation technologies in neurodegenerative diseases constitute a powerful tool that significantly contributes to patients’ diagnosis.

Predicting the therapeutic response to ocular hypotensive drugs is crucial for the clinical treatment and management of glaucoma. Our aim was to identify a possible genetic contribution to the response to current pharmacological treatments of choice in a white Mediterranean population with primary open-angle glaucoma (POAG) or ocular hypertension (OH). We conducted a prospective, controlled, randomized, partial crossover study that included 151 patients of both genders, aged 18 years and older, diagnosed with and requiring pharmacological treatment for POAG or OH in one or both eyes. We sought to identify copy number variants (CNVs) associated with differences in pharmacological response, using a DNA pooling strategy of carefully phenotyped treatment responders and non-responders, treated for a minimum of 6 weeks with a beta-blocker (timolol maleate) and/or prostaglandin analog (latanoprost). Diurnal intraocular pressure reduction and comparative genome wide CNVs were analyzed. Our finding that copy number alleles of an intronic portion of the MLIP gene is a predictor of pharmacological response to beta blockers and prostaglandin analogs could be used as a biomarker to guide first-tier POAG and OH treatment. Our finding improves understanding of the genetic factors modulating pharmacological response in POAG and OH, and represents an important contribution to the establishment of a personalized approach to the treatment of glaucoma.

Next-generation sequencing (NGS) has the capacity of carrier screening in gamete donation (GD) programs. We have developed and validated an NGS carrier-screening test (qCarrier test) that includes 200 genes associated with 368 disorders (277 autosomal recessive and 37 X-linked). Carrier screening is performed on oocyte donation candidates and the male partner of oocyte recipient. Carriers of X-linked conditions are excluded from the GD program, whereas donors are chosen who do not carry mutations for the same gene/disease as the recipients. The validation phase showed a high sensitivity (>99% sensitivity) detecting all single-nucleotide variants, 13 indels, and 25 copy-number variants included in the validation set. A total of 1,301 individuals were analysed with the qCarrier test, including 483 candidate oocyte donors and 635 receptor couples, 105 females receiving sperm donation, and 39 couples seeking pregnancy. We identified 56% of individuals who are carriers for at least one genetic condition and 1.7% of female donors who were excluded from the program due to a carrier state of X-linked conditions. Globally, 3% of a priori assigned donations had a high reproductive risk that could be minimized after testing. Genetic counselling at different stages is essential for helping to facilitate a successful and healthy pregnancy.

This is an open access article under the terms of the Creative Commons Attribution-NonCommercial License.-- et al., Chronic lymphocytic leukemia (CLL) is a common disease with highly variable clinical course. Several recurrent chromosomal alterations are associated with prognosis and may guide risk-adapted therapy. We have developed a targeted genome-wide array to provide a robust tool for ascertaining abnormalities in CLL and to overcome limitations of the 4-marker fluorescence in situ hybridization (FISH). DNA from 180 CLL patients were hybridized to the qChip®Hemo array with a high density of probes covering commonly altered loci in CLL (11q22-q23, 13q14, and 17p13), nine focal regions (2p15-p16.1, 2p24.3, 2q13, 2q36.3-q37.1, 3p21.31, 8q24.21, 9p21.3, 10q24.32, and 18q21.32-q21.33) and two larger regions (6q14.1-q22.31 and 7q31.33-q33). Overall, 86% of the cases presented copy number alterations (CNA) by array. There was a high concordance of array findings with FISH (84% sensitivity, 100% specificity); all discrepancies corresponded to subclonal alterations detected only by FISH. A chromothripsis-like pattern was detected in eight cases. Three showed concomitant shattered 5p with gain of TERT along with isochromosome 17q. Presence of 11q loss was associated with shorter time to first treatment (P=0.003), whereas 17p loss, increased genomic complexity, and chromothripsis were associated with shorter overall survival (P, Supported by: Fondo de Investigaciones Sanitarias, Instituto de Salud Carlos III (ISCIII), Grant numbers: PI11/01177, PI14/00571; Worldwide Cancer Research; Grant number: 12-0142; Marato de TV3; Grant number: TV3-Cancer/2013410; Generalitat de Catalunya Suport Grups de Recerca; Grant number: 2013-SGR-378; Red Tematica de Investigacion Cooperativa en Cancer (RTICC), Grant numbers: RD12/0036/0036, RD12/0036/0023, RD12/0036/0004, RD12/0036/0069; Subprograma Juan de la Cierva, Grant number: JCI-2011-10232; Miguel Servet Contract, Grant number: CP13/00159; the Spanish Ministry of Science and Innovation (MICINN) through the ISCIII —International Cancer Genome Consortium for Chronic Lymphocytic Leukemia (ICGC-CLL Genome Project); Institucio Catalana de Recerca i Estudis Avançats” (ICREA) of the Generalitat de Catalunya; European Regional Development Fund “Una manera de fer Europa”; Alexander von Humboldt Post-doctoral Fellowship.

Progression of non-alcoholic fatty liver disease (NAFLD) in the context of metabolic syndrome (MetS) is only partially explored due to the lack of preclinical models. In order to study the alterations in hepatic metabolism that accompany this condition, we developed a model of MetS accompanied by the onset of steatohepatitis (NASH) by challenging golden hamsters with a high-fat diet low in vitamin E and selenium (HFD), since combined deficiency results in hepatic necroinflammation in rodents. Metabolomics and transcriptomics integrated analyses of livers revealed an unexpected accumulation of hepatic S-Adenosylmethionine (SAM) when compared with healthy livers likely due to diminished methylation reactions and repression of GNMT. SAM plays a key role in the maintenance of cellular homeostasis and cell cycle control. In agreement, analysis of over-represented transcription factors revealed a central role of c-myc and c-Jun pathways accompanied by negative correlations between SAM concentration, MYC expression and AMPK phosphorylation. These findings point to a drift of cell cycle control toward senescence in livers of HFD animals, which could explain the onset of NASH in this model. In contrast, hamsters with NAFLD induced by a conventional high-fat diet did not show SAM accumulation, suggesting a key role of selenium and vitamin E in SAM homeostasis. In conclusion, our results suggest that progression of NAFLD in the context of MetS can take place even in a situation of hepatic SAM excess and that selenium and vitamin E status might be considered in current therapies against NASH based on SAM supplementation.

Background Here we have developed a novel and much more efficient strategy for the complete molecular characterisation of the cystic fibrosis (CF) transmembrane regulator (CFTR) gene, based on multiplexed targeted resequencing. We have tested this approach in a cohort of 92 samples with previously characterised CFTR mutations and polymorphisms. Methods After enrichment of the pooled barcoded DNA libraries with a custom NimbleGen SeqCap EZ Choice array (Roche) and sequencing with a HiSeq2000 (Illumina) sequencer, we applied several bioinformatics tools to call mutations and polymorphisms in CFTR. Results The combination of several bioinformatics tools allowed us to detect all known pathogenic variants (point mutations, short insertions/deletions, and large genomic rearrangements) and polymorphisms (including the poly-T and poly-thymidine-guanine polymorphic tracts) in the 92 samples. In addition, we report the precise characterisation of the breakpoints of seven genomic rearrangements in CFTR, including those of a novel deletion of exon 22 and a complex 85 kb inversion which includes two large deletions affecting exons 4–8 and 12–21, respectively. Conclusions This work is a proof-of-principle that targeted resequencing is an accurate and cost-effective approach for the genetic testing of CF and CFTR-related disorders (ie, male infertility) amenable to the routine clinical practice, and ready to substitute classical molecular methods in medical genetics.

Genetic diagnostics of phenylketonuria (PKU) and tetrahydrobiopterin (BH4) deficient hyperphenylalaninemia (BH4DH) rely on methods that scan for known mutations or on laborious molecular tools that use Sanger sequencing. We have implemented a novel and much more efficient strategy based on high-throughput multiplex-targeted resequencing of four genes (PAH, GCH1, PTS, and QDPR) that, when affected by loss-of-function mutations, cause PKU and BH4DH. We have validated this approach in a cohort of 95 samples with the previously known PAH, GCH1, PTS, and QDPR mutations and one control sample. Pooled barcoded DNA libraries were enriched using a custom NimbleGen SeqCap EZ Choice array and sequenced using a HiSeq2000 sequencer. The combination of several robust bioinformatics tools allowed us to detect all known pathogenic mutations (point mutations, short insertions/deletions, and large genomic rearrangements) in the 95 samples, without detecting spurious calls in these genes in the control sample. We then used the same capture assay in a discovery cohort of 11 uncharacterized HPA patients using a MiSeq sequencer. In addition, we report the precise characterization of the breakpoints of four genomic rearrangements in PAH, including a novel deletion of 899 bp in intron 3. Our study is a proof-of-principle that high-throughput-targeted resequencing is ready to substitute classical molecular methods to perform differential genetic diagnosis of hyperphenylalaninemias, allowing the establishment of specifically tailored treatments a few days after birth.

Microarray technology, recently implemented in international prenatal diagnosis systems, has become one of the main techniques in this field in terms of detection rate and objectivity of the results. This guideline attempts to provide background information on this technology, including technical and diagnostic aspects to be considered. Specifically, this guideline defines: the different prenatal sample types to be used, as well as their characteristics (chorionic villi samples, amniotic fluid, fetal cord blood or miscarriage tissue material); variant reporting policies (including variants of uncertain significance) to be considered in informed consents and prenatal microarray reports; microarray limitations inherent to the technique and which must be taken into account when recommending microarray testing for diagnosis; a detailed clinical algorithm recommending the use of microarray testing and its introduction into routine clinical practice within the context of other genetic tests, including pregnancies in families with a genetic history or specific syndrome suspicion, first trimester increased nuchal translucency or second trimester heart malformation and ultrasound findings not related to a known or specific syndrome. This guideline has been coordinated by the Spanish Association for Prenatal Diagnosis (AEDP, «Asociacion Espanola de Diagnostico Prenatal»), the Spanish Human Genetics Association (AEGH, «Asociacion Espanola de Genetica Humana») and the Spanish Society of Clinical Genetics and Dysmorphology (SEGCyD, «Sociedad Espanola de Genetica Clinica y Dismorfologia»).

Resumen El desarrollo en los ultimos anos de las denominadas tecnologias de secuenciacion masiva permite actualmente obtener millones de secuencias de ADN a una velocidad sin precedentes y a un coste cada vez mas reducido. Estas tecnologias estan permitiendo la consecucion de logros cientificos trascendentales, con la identificacion de nuevos genes y la resolucion de las bases geneticas de enfermedades mendelianas a la cabeza. Su potencial ha permitido el desarrollo de nuevas aplicaciones y pruebas biologicas que van a revolucionar, en un futuro proximo, el diagnostico postnatal y prenatal de enfermedades geneticas. En el presente articulo se ofrece una vision general de la tecnologia y se examinan sus ventajas e inconvenientes respecto a metodos convencionales asi como algunas de las principales estrategias, incluyendo metodos de estrategias de diagnostico prenatal dirigidas a la deteccion de aneuploidias y sindromes de delecion/duplicacion.

Nicotinic acetylcholine receptors (nAChRs) are ligand-gated pentameric ion channels that account for the effects of nicotine. Recent genetic studies have highlighted the importance of variants of the CHRNA5/A3/B4 genomic cluster in human nicotine dependence. Among these genetic variants those found in non-coding segments of the cluster may contribute to the pathophysiology of tobacco use through alterations in the expression of these genes. To discern the in vivo effects of the cluster, we generated a transgenic mouse overexpressing the human CHRNA5/A3/B4 cluster using a bacterial artificial chromosome. Transgenic mice showed increased functional a3b4-nAChRs in brain regions where these subunits are highly expressed under normal physiological conditions. Moreover, they exhibited increased sensitivity to the pharmacological effects of nicotine along with higher activation of the medial habenula and reduced activation of dopaminergic neurons in the ventral tegmental area after acute nicotine administration. Importantly, transgenic mice showed increased acquisition of nicotine self-administration (0.015 mg/kg per infusion) and a differential response in the progressive ratio test. Our study provides the first in vivo evidence of the involvement of the CHRNA5/A3/B4 genomic cluster in nicotine addiction through modifying the activity of brain regions responsible for the balance between the rewarding and the aversive properties of this drug. © Springer-Verlag 2011., This work was funded by the Catalan Government (2009SGR1313) Spanish Ministry of Education and Sciences SAF2007-60827, SAF2007-31093-E, SAF2010-16427; Phecomp (EU LSHM-CT-2007-037669), EU/FIS PS09102673, ERARare, Ministerio de Salud y Consumo (RTA G03/005, PI05/0513 and PI082038), University of the Basque Country (1/UPV 0026.327-E-15924/2004) and Plan Nacional sobre Drogas (PNDMSC 2005), Fundacion Ramón Areces, Reina Sofía, Marató TV3, and CIBERER. P. M. is a scientific researcher supported by the Juan de la Cierva program of Ministerio de Ciencia e Innovación, and a grant from the National Institutes on Drug Abuse (R01 DA003194 to MJM).

Background Copy number variations (CNV) have become an important source of human genome variability noteworthy to consider when studying genetic susceptibility to complex diseases. As recent studies have found evidences for the potential involvement of CNVs in psychiatric disorders, we have studied the dosage effect of structural genome variants as a possible susceptibility factor for different psychiatric disorders in a candidate gene approach. Methods After selection of 68 psychiatric disorders’ candidate genes overlapping with CNVs, MLPA assays were designed to determine changes in copy number of these genes. The studied sample consisted of 724 patients with psychiatric disorders (accounting for anxiety disorders, mood disorders, eating disorders and schizophrenia) and 341 control individuals. Results CNVs were detected in 30 out of the 68 genes screened, indicating that a considerable proportion of neuronal pathways genes contain CNVs. When testing the overall burden of rare structural genomic variants in the different psychiatric disorders compared to control individuals, there was no statistically significant difference in the total amount of gains and losses. However, 14 out of the 30 changes were only found in psychiatric disorder patients but not in control individuals. These genes include GRM7, previously associated to major depression disorder and bipolar disorder, SLC6A13, in anxiety disorders, and S100B, SSTR5 and COMT in schizophrenia. Conclusions Although we have not been able to found a clear association between the studied CNVs and psychiatric disorders, the rare variants found only within the patients could account for a step further towards understanding the pathophysiology of psychiatric disorders.

Developments in quantitative PCR technologies have greatly improved our ability to detect large genome rearrangements. In particular oligonucleotide-based array comparative genomic hybridisation has become a useful tool for appropriate and rapid detection of breakpoints. In this work, we have analysed 80 samples (42 unknown CF alleles) applying three quantitative technologies (MLPA, qPCR and array-CGH) to detect recurrent as well as novel large rearrangements in the Spanish CF population. Three deletions and one duplication have been identified in five alleles (12%). Interestingly, we provide the comprehensive characterisation of the first duplication in our CF cohort. The new CFTRdupProm-3 mutation spans 35.7 kb involving the 5'-end of the CFTR gene. Additionally, the RNA analysis has revealed a cryptic sequence with a premature termination codon leading to a disrupted protein. This duplication has been identified in five unrelated families from Spain, France and Italy with all patients showing the same associated haplotype, which is further evidence for its likely common Mediterranean origin. Overall, considering this and other previous studies, CFTR rearrangements account for 1.3% of the Spanish CF alleles.

We report on a girl with mild dysmorphic facial features, Dandy–Walker malformation (DWM), iris coloboma, profound hearing loss, and hyperlaxity of skin and joints, whose karyotype is 46,XX,t(6;13)(q23;q32)dn and who has a cryptic imbalance at the 13q32 translocation breakpoint assessed by array-CGH. Our patient has many clinical manifestations in common with those of the previously reported cases of 13q32 deletions, which suggests that at least part of the abnormal phenotype is probably due to the imbalance. The recurrent finding of DWM among patients with 13q deletions has led to the suggestions that candidate gene/s for its development are on chromosome 13. We describe the smallest 13q deletion associated to DWM, which allows further narrowing of the previously established critical region for this brain malformation to 13q32.2-32.3. Among the few genes of the deleted region, ZIC2 and ZIC5 seem the most plausible candidates, which is in keeping with some previous reports. This work also illustrates the usefulness of array-CGH platforms in the identification of cryptic imbalances in carriers of apparently balanced rearrangements with abnormal phenotypes. © 2010 Wiley-Liss, Inc.

Mosaicism is defined as the coexistence of cells with different genetic composition within an individual, caused by postzygotic somatic mutation. Although somatic mosaicism for chromosomal abnormalities is a well-established cause of developmental and somatic disorders and has also been detected in different tissues, its frequency and extent in the adult normal population are still unknown. We provide here a genome-wide survey of mosaic genomic variation obtained by analyzing Illumina 1M SNP array data from blood or buccal DNA samples of 1991 adult individuals from the Spanish Bladder Cancer/EPICURO genome-wide association study. We found mosaic abnormalities in autosomes in 1.7% of samples, including 23 segmental uniparental disomies, 8 complete trisomies, and 11 large (1.5-37 Mb) copy-number variants. Alterations were observed across the different autosomes with recurrent events in chromosomes 9 and 20. No case-control differences were found in the frequency of events or the percentage of cells affected, thus indicating that most rearrangements found are not central to the development of bladder cancer. However, five out of six events tested were detected in both blood and bladder tissue from the same individual, indicating an early developmental origin. The high cellular frequency of the anomalies detected and their presence in normal adult individuals suggest that this type of mosaicism is a widespread phenomenon in the human genome. Somatic mosaicism should be considered in the expanding repertoire of inter- and intraindividual genetic variation, some of which may cause somatic human diseases but also contribute to modifying inherited disorders and/or late-onset multifactorial traits. © 2010 The American Society of Human Genetics. All rights reserved., This work was supported by the Intramural Research Program of the NCI Division of Cancer Epidemiology and Genetics (to N.R., D.S., and S.J.C.), the Asociacion Espanola Contra el Cancer (to F.X.R., N.M., and L.A.P.-J.), EU-6FP grants LSHG-CT-2006-037627 (to L.A.P.-J.) and HEALTH-STREP-2006-037739-DropTop (to N.M. and F.X.R.), Fondo de Investigacion Sanitaria grants PI076832 (to L.A.P.-J.) and PI061614 (to F.X.R.), Consolider ONCOBIO (to F.X.R.), National Institutes of Health grant R01 CA089715-06A2 (to N.M. and F.X.R.), Red Tematica de Investigacion Cooperativa en Cancer (to N.M. and A.C.), Fundacio La Marato de TV3 (to N.M.), and EU-7FP grant agreements #201663-UROMOL (to N.M. and F.X.R.) and #201333-DECanBIO (to N.M.). B.R.-S. and G.M. were supported by a postdoctoral fellowship (FIS CD06/00019) and a predoctoral fellowship (FI09/00205) of the Fondo Investigación Sanitaria, respectively.

Contains fulltext : 80084.pdf (Publisher’s version ) (Closed access) Psoriasis is a common inflammatory skin disease with a prevalence of 2-3% in individuals of European ancestry. In a genome-wide search for copy number variants (CNV) using a sample pooling approach, we have identified a deletion comprising LCE3B and LCE3C, members of the late cornified envelope (LCE) gene cluster. The absence of LCE3B and LCE3C (LCE3C_LCE3B-del) is significantly associated (P = 1.38E-08) with risk of psoriasis in 2,831 samples from Spain, The Netherlands, Italy and the United States, and in a family-based study (P = 5.4E-04). LCE3C_LCE3B-del is tagged by rs4112788 (r(2) = 0.93), which is also strongly associated with psoriasis (P < 6.6E-09). LCE3C_LCE3B-del shows epistatic effects with the HLA-Cw6 allele on the development of psoriasis in Dutch samples and multiplicative effects in the other samples. LCE expression can be induced in normal epidermis by skin barrier disruption and is strongly expressed in psoriatic lesions, suggesting that compromised skin barrier function has a role in psoriasis susceptibility.

Interstitial deletions of the short arm of chromosome 3 are rare, and a specific clinical phenotype has not been defined. We report the first isolated cryptic proximal interstitial 3p deletion, del(3)(p12.3p13), assessed by array-based comparative genomic hybridization in a girl with an inversion of chromosome 7, whose phenotype includes neurodevelopmental delay, growth retardation, dysmorphic facial features, hypophysis hypoplasia, gastroesophageal reflux, clinodactyly, preauricular appendix, and myopia. Her features are similar to those observed in the previously reported cases of proximal 3p deletions overlapping with our imbalance, indicating that her clinical manifestations are likely to be due to the deletion. As our patient’s imbalance is the first non-cytogenetically visible proximal interstitial 3p deletion uncomplicated by other imbalances, its characterization has allowed us to narrow the minimal deletion interval associated with growth retardation and neurodevelopmental delay to the 3p12.3–p13 region. Among the genes found in this region, ROBO1, ROBO2, PDZRN3 and CNTN3 might play a role in the neurodevelopmental delay of the patient. This study provides additional evidence that cryptic imbalances anywhere along the genome can be found in patients with phenotypic abnormalities and a balanced chromosome rearrangement.

Genomes contain a large number of genes that do not have recognizable homologues in other species and that are likely to be involved in important species-specific adaptive processes. The origin of many such "orphan" genes remains unknown. Here we present the first systematic study of the characteristics and mechanisms of formation of primate-specific orphan genes. We determine that codon usage values for most orphan genes fall within the bulk of the codon usage distribution of bona fide human proteins, supporting their current protein-coding annotation. We also show that primate orphan genes display distinctive features in relation to genes of wider phylogenetic distribution: higher tissue specificity, more rapid evolution, and shorter peptide size. We estimate that around 24% are highly divergent members of mammalian protein families. Interestingly, around 53% of the orphan genes contain sequences derived from transposable elements (TEs) and are mostly located in primate-specific genomic regions. This indicates frequent recruitment of TEs as part of novel genes. Finally, we also obtain evidence that a small fraction of primate orphan genes, around 5.5%, might have originated de novo from mammalian noncoding genomic regions.

The assessment of the association between a candidate locus and a disease may require the assumption of an inheritance model. Most researchers select the additive model and test the association with the Cochran-Armitage trend test. This test assumes a dose-response effect with regard to the number of copies of the variant allele. However, if there is reason to expect dominance or recessiveness in the effect of the variant allele, the heterozygous genotype may be grouped with one of the two homozygous, depending on the inheritance model, and a simple test on the 2 x 2 table can be used to assess independence. When the underlying genetic model is unknown, association may be assessed using the max-statistic, which selects the largest test statistic from the dominant, recessive and additive models. The statistical significance of the max-statistic has been previously addressed using permutation or Monte Carlo simulation approaches. We aimed to provide simpler alternatives to the max-test to make it feasible in large-scale association studies. Our simulations show that this procedure has an effective number of tests of 2.2, which can be used to correct the significance level or P-values. We also derive the asymptotic distribution of max-statistic, which leads to a simple way to calculate the significance level and allows the derivation of a formula for power calculations in the design of studies that plan to use the max-statistic. A simulation study shows that the use of the max-statistic is a powerful approach that provides safeguard against model uncertainty.

BackgroundCurrent screening for carriers of genetic diseases in oocyte donors includes the assessment of risk of transmission of inherited diseases based on personal and family history of genetic disorders. Most assisted reproduction centers also include karyotyping, mutational screening of the CFTR gene and directed the study of fragile X premutation. Next generation sequencing (NGS) technologies of have allowed to expand genetic screening to a large number of diseases at a reasonable cost.Objective • Develop a new genetic test (qCarrier) based on NGS technology for extended recessive diseases in the field of reproductive medicine screening. • Implementation of the carrier screening test in our oocyte donation program.Material and MethodsThe test covers 200 genes (68 in full sequence analysis and targeted screening of 132 known mutations) associated with autosomal recessive diseases 185 (AR) and 11 linked to chromosome X. The test was developed by NGS technology and allows characterization of a broad spectrum of mutations (point, indels, rearrangements and CNVs). The expanded carrier screening is performed on all candidate of oocyte donors and on the male partner of the recipient of oocytes. We discard from the oocyte donor program all candidates that are carriers of X-linked disease. The heterozygous carrier status for an autosomal recessive condition is no a reason for exclusion as a donor, but it involves the selection of a recipient whose male partner is not a carrier of disease mutations in the same gene.ResultsThe validation of the test showed high sensitivity (>99%). It has made the extended carrier screening a total of 445 oocyte donor candidates and a total of 587 male partners of oocyte recipients. The implementation of the test in our OD program has identified 57% of patients/donors carriers least a pathogenic mutation.Conclusions • The implementation of the test in oocyte donors program has identified a 3% allocation at high risk of disease autosomal recessive. Two percent of donor candidates to enter the oocyte donors program are carriers of pathogenic mutations linked to the X chromosome. • The expanded carrier screening is a useful tool to reduce the rate of newborns affected of genetic diseases in children born through oocyte donors program. • The implementation of the test in clinical settings requires pre and post-test genetic counseling to ensure adequate information, consent of patients and safeguard the fundamental ethical issues facing patients and oocyte donors.

Genome-wide association scans (GWASs) using single nucleotide polymorphisms (SNPs) have been completed successfully for several common disorders and have detected over 30 new associations. Considering the large sample sizes and genome-wide SNP coverage of the scans, one might have expected many of the common variants underpinning the genetic component of various disorders to have been identified by now. However, these studies have not evaluated the contribution of other forms of genetic variation, such as structural variation, mainly in the form of copy number variants (CNVs). Known CNVs account for over 15% of the assembled human genome sequence. Since CNVs are not easily tagged by SNPs, might have a wide range of copy number variability, and often fall in genomic regions not well covered by whole-genome arrays or not genotyped by the HapMap project, current GWASs have largely missed the contribution of CNVs to complex disorders. In fact, some CNVs have already been reported to show association with several complex disorders using candidate gene/region approaches, underpinning the importance of regions not investigated in current GWASs. This reveals the need for new generation arrays (some already in the market) and the use of tailored approaches to explore the full dimension of genome variability beyond the single nucleotide scale.

Genomic plasticity of human chromosome 8p23.1 region is highly influenced by two groups of complex segmental duplications (SDs), termed REPD and REPP, that mediate different kinds of rearrangements. Part of the difficulty to explain the wide range of phenotypes associated with 8p23.1 rearrangements is that REPP and REPD are not yet well characterized, probably due to their polymorphic status. Here, we describe a novel primate-specific gene family, named FAM90A (family with sequence similarity 90), found within these SDs. According to the current human reference sequence assembly, the FAM90A family includes 24 members along 8p23.1 region plus a single member on chromosome 12p13.31, showing copy number variation (CNV) between individuals. These genes can be classified into subfamilies I and II, which differ in their upstream and 5′-untranslated region sequences, but both share the same open reading frame and are ubiquitously expressed. Sequence analysis and comparative fluorescence in situ hybridization studies showed that FAM90A subfamily II suffered a big expansion in the hominoid lineage, whereas subfamily I members were likely generated sometime around the divergence of orangutan and African great apes by a fusion process. In addition, the analysis of the Ka/Ks ratios provides evidence of functional constraint of some FAM90A genes in all species. The characterization of the FAM90A gene family contributes to a better understanding of the structural polymorphism of the human 8p23.1 region and constitutes a good example of how SDs, CNVs and rearrangements within themselves can promote the formation of new gene sequences with potential functional consequences.

Numerous types of DNA variation exist, ranging from SNPs to larger structural alterations such as copy number variants (CNVs) and inversions. Alignment of DNA sequence from different sources has been used to identify SNPs1,2 and intermediate-sized variants (ISVs)3. However, only a small proportion of total heterogeneity is characterized, and little is known of the characteristics of most smaller-sized (1.5 million SNPs. Some differences were simple insertions and deletions, but in regions containing CNVs, segmental duplication and repetitive DNA, they were more complex. Our results uncover substantial undescribed variation in humans, highlighting the need for comprehensive annotation strategies to fully interpret genome scanning and personalized sequencing projects.