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We report a series of four unrelated adults with Smith-Magenis syndrome (SMS) and concomitant features of Birt-Hogg-Dubé (BHD) syndrome based upon haploinsufficiency for FLCN and characteristic renal cell carcinomas and/or evidence of cutaneous fibrofolliculomas. Three of the cases constitute the first known association of histopathologically verified characteristic BHD-associated renal tumors in adults with SMS; the fourth was identified to have histologically confirmed skin fibrofolliculomas. Molecular analysis documented second-hit FLCN mutations in two of the three cases with confirmed BHD renal pathology. These cases suggest the need to expand management recommendations for SMS to include kidney cancer surveillance starting at 20 years of age, as per the screening recommendations for BHD syndrome.
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Síndrome de Birt-Hogg-Dubé , Carcinoma de Células Renales , Neoplasias Renales , Neoplasias Cutáneas , Síndrome de Smith-Magenis , Adulto , Humanos , Síndrome de Birt-Hogg-Dubé/complicaciones , Síndrome de Birt-Hogg-Dubé/diagnóstico , Síndrome de Birt-Hogg-Dubé/genética , Síndrome de Smith-Magenis/complicaciones , Detección Precoz del Cáncer , Proteínas Proto-Oncogénicas/genética , Proteínas Supresoras de Tumor/genética , Neoplasias Renales/genética , Carcinoma de Células Renales/genética , Neoplasias Cutáneas/genéticaRESUMEN
The recent description of biallelic DNAJC30 variants in Leber hereditary optic neuropathy (LHON) and Leigh syndrome challenged the longstanding assumption for LHON to be exclusively maternally inherited and broadened the genetic spectrum of Leigh syndrome, the most frequent paediatric mitochondrial disease. Herein, we characterize 28 so far unreported individuals from 26 families carrying a homozygous DNAJC30 p.Tyr51Cys founder variant, 24 manifesting with LHON, two manifesting with Leigh syndrome, and two remaining asymptomatic. This collection of unreported variant carriers confirms sex-dependent incomplete penetrance of the homozygous variant given a significant male predominance of disease and the report of asymptomatic homozygous variant carriers. The autosomal recessive LHON patients demonstrate an earlier age of disease onset and a higher rate of idebenone-treated and spontaneous recovery of vision in comparison to reported figures for maternally inherited disease. Moreover, the report of two additional patients with childhood- or adult-onset Leigh syndrome further evidences the association of DNAJC30 with Leigh syndrome, previously only reported in a single childhood-onset case.
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Enfermedad de Leigh , Atrofia Óptica Hereditaria de Leber , Adulto , Niño , ADN Mitocondrial/genética , Femenino , Humanos , Enfermedad de Leigh/genética , Masculino , Mutación/genética , Atrofias Ópticas Hereditarias , Atrofia Óptica Hereditaria de Leber/genéticaRESUMEN
PURPOSE: To elucidate the novel molecular cause in families with a new autosomal recessive neurodevelopmental disorder. METHODS: A combination of exome sequencing and gene matching tools was used to identify pathogenic variants in 17 individuals. Quantitative reverse transcription polymerase chain reaction (RT-qPCR) and subcellular localization studies were used to characterize gene expression profile and localization. RESULTS: Biallelic variants in the TMEM222 gene were identified in 17 individuals from nine unrelated families, presenting with intellectual disability and variable other features, such as aggressive behavior, shy character, body tremors, decreased muscle mass in the lower extremities, and mild hypotonia. We found relatively high TMEM222 expression levels in the human brain, especially in the parietal and occipital cortex. Additionally, subcellular localization analysis in human neurons derived from induced pluripotent stem cells (iPSCs) revealed that TMEM222 localizes to early endosomes in the synapses of mature iPSC-derived neurons. CONCLUSION: Our findings support a role for TMEM222 in brain development and function and adds variants in the gene TMEM222 as a novel underlying cause of an autosomal recessive neurodevelopmental disorder.
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Discapacidad Intelectual , Trastornos del Neurodesarrollo , Humanos , Discapacidad Intelectual/genética , Trastornos del Neurodesarrollo/genética , Linaje , Secuenciación del ExomaRESUMEN
Int22h1/Int22h2-mediated Xq28 duplication syndrome is a relatively new X-linked intellectual disability syndrome, arising from duplications of the subregion flanked by intron 22 homologous regions 1 and 2 on the q arm of chromosome X. Its primary manifestations include variable cognitive deficits, distinct facial dysmorphia, and neurobehavioral abnormalities that mainly include hyperactivity, irritability, and autistic behavior. Affected males are hemizygous for the duplication, which explains their often more severe manifestations compared with heterozygous females. In this report, we describe the cases of nine individuals recently identified having the syndrome, highlighting unique and previously unreported findings of this syndrome. Specifically, we report for the first time in this syndrome, two cases with de novo duplications, three receiving prenatal diagnosis with the syndrome, and three others having atypical versions of the duplication. Among the latter, one proband has a shortened version spanning only the centromeric half of the typical duplication, while the other two cases have a nearly identical length duplication as the classical duplication, with the exception that their duplication's breakpoints are telomerically shifted by about 0.2 Mb. Finally, we shed light on two new manifestations in this syndrome, vertebral anomalies and multiple malignancies, which possibly expand the phenotypic spectrum of the syndrome.
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Duplicación Cromosómica , Enfermedades Genéticas Ligadas al Cromosoma X/genética , Discapacidad Intelectual/genética , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Diagnóstico Prenatal , SíndromeRESUMEN
The original version of this Article contained an error in the spelling of the author J. Lawrence Merritt, which was incorrectly given as Lawrence Merritt. This has now been corrected in both the PDF and HTML versions of the Article.
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PURPOSE: TANGO2-related disorders were first described in 2016 and prior to this publication, only 15 individuals with TANGO2-related disorder were described in the literature. Primary features include metabolic crisis with rhabdomyolysis, encephalopathy, intellectual disability, seizures, and cardiac arrhythmias. We assess whether genotype and phenotype of TANGO2-related disorder has expanded since the initial discovery and determine the efficacy of exome sequencing (ES) as a diagnostic tool for detecting variants. METHODS: We present a series of 14 individuals from 11 unrelated families with complex medical and developmental histories, in whom ES or microarray identified compound heterozygous or homozygous variants in TANGO2. RESULTS: The initial presentation of patients with TANGO2-related disorders can be variable, including primarily neurological presentations. We expand the phenotype and genotype for TANGO2, highlighting the variability of the disorder. CONCLUSION: TANGO2-related disorders can have a more diverse clinical presentation than previously anticipated. We illustrate the utility of routine ES data reanalysis whereby discovery of novel disease genes can lead to a diagnosis in previously unsolved cases and the need for additional copy-number variation analysis when ES is performed.
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Translocador Nuclear del Receptor de Aril Hidrocarburo/genética , Adolescente , Translocador Nuclear del Receptor de Aril Hidrocarburo/fisiología , Encefalopatías/genética , Niño , Preescolar , Variaciones en el Número de Copia de ADN/genética , Discapacidades del Desarrollo/genética , Exoma , Familia , Femenino , Genotipo , Humanos , Discapacidad Intelectual/genética , Masculino , Linaje , Fenotipo , Convulsiones/genética , Secuenciación del Exoma/métodosRESUMEN
SATB2-associated syndrome (SAS) is an autosomal dominant disorder characterized by significant neurodevelopmental disabilities with limited to absent speech, behavioral issues, and craniofacial anomalies. Previous studies have largely been restricted to case reports and small series without in-depth phenotypic characterization or genotype-phenotype correlations. Seventy two study participants were identified as part of the SAS clinical registry. Individuals with a molecularly confirmed diagnosis of SAS were referred after clinical diagnostic testing. In this series we present the most comprehensive phenotypic and genotypic characterization of SAS to date, including prevalence of each clinical feature, neurodevelopmental milestones, and when available, patient management. We confirm that the most distinctive features are neurodevelopmental delay with invariably severely limited speech, abnormalities of the palate (cleft or high-arched), dental anomalies (crowding, macrodontia, abnormal shape), and behavioral issues with or without bone or brain anomalies. This comprehensive clinical characterization will help clinicians with the diagnosis, counseling and management of SAS and help provide families with anticipatory guidance.
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Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Genotipo , Proteínas de Unión a la Región de Fijación a la Matriz/genética , Fenotipo , Factores de Transcripción/genética , Anomalías Múltiples/diagnóstico , Anomalías Múltiples/genética , Adolescente , Adulto , Niño , Preescolar , Facies , Femenino , Estudios de Asociación Genética/métodos , Humanos , Lactante , Patrón de Herencia , Masculino , Polimorfismo de Nucleótido Simple , Síndrome , Adulto JovenRESUMEN
Horstick et al. (2013) previously reported a homozygous p.Trp284Ser variant in STAC3 as the cause of Native American myopathy (NAM) in 5 Lumbee Native American families with congenital hypotonia and weakness, cleft palate, short stature, ptosis, kyphoscoliosis, talipes deformities, and susceptibility to malignant hyperthermia (MH). Here we present two non-Native American families, who were found to have STAC3 pathogenic variants. The first proband and her affected older sister are from a consanguineous Qatari family with a suspected clinical diagnosis of Carey-Fineman-Ziter syndrome (CFZS) based on features of hypotonia, myopathic facies with generalized weakness, ptosis, normal extraocular movements, cleft palate, growth delay, and kyphoscoliosis. We identified the homozygous c.851G>C;p.Trp284Ser variant in STAC3 in both sisters. The second proband and his affected sister are from a non-consanguineous, Puerto Rican family who was evaluated for a possible diagnosis of Moebius syndrome (MBS). His features included facial and generalized weakness, minimal limitation of horizontal gaze, cleft palate, and hypotonia, and he has a history of MH. The siblings were identified to be compound heterozygous for STAC3 variants c.851G>C;p.Trp284Ser and c.763_766delCTCT;p.Leu255IlefsX58. Given the phenotypic overlap of individuals with CFZS, MBS, and NAM, we screened STAC3 in 12 individuals diagnosed with CFZS and in 50 individuals diagnosed with MBS or a congenital facial weakness disorder. We did not identify any rare coding variants in STAC3. NAM should be considered in patients presenting with facial and generalized weakness, normal or mildly abnormal extraocular movement, hypotonia, cleft palate, and scoliosis, particularly if there is a history of MH.
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Proteínas Adaptadoras Transductoras de Señales/genética , Síndrome de Mobius/genética , Enfermedades Musculares/genética , Mutación , Síndrome de Pierre Robin/genética , Adolescente , Adulto , Niño , Femenino , Humanos , Masculino , Síndrome de Mobius/complicaciones , Síndrome de Mobius/patología , Enfermedades Musculares/complicaciones , Enfermedades Musculares/patología , Linaje , Síndrome de Pierre Robin/complicaciones , Síndrome de Pierre Robin/patología , Pronóstico , Adulto JovenRESUMEN
Mutations in PIGN, resulting in multiple congenital anomalies-hypotonia-seizures syndrome, a glycosylphosphatidylinositol anchor deficiency, have been published in four families to date. We report four patients from three unrelated families with epilepsy and hypotonia in whom whole exome sequencing yielded compound heterozygous variants in PIGN. As with previous reports Patients 1 and 2 (full siblings) have severe global developmental delay, gastroesophageal reflux disease, and minor dysmorphic features, including high palate, bitemporal narrowing, depressed nasal bridge, and micrognathia; Patient 3 had early global developmental delay with later progressive spastic quadriparesis, intellectual disability, and intractable generalized epilepsy; Patient 4 had bilateral narrowing as well but differed by the presence of hypertelorism, markedly narrow palpebral fissures, and long philtrum, had small distal phalanges of fingers 2, 3, and 4, absent distal phalanx of finger 5 and similar toe anomalies, underdeveloped nails, unusual brain anomalies, and a more severe early clinical course. These patients expand the known clinical spectrum of the disease. The severity of the presentations in conjunction with the patients' mutations suggest a genotype-phenotype correlation in which congenital anomalies are only seen in patients with biallelic loss-of-function. In addition, PIGN mutations appear to be panethnic and may be an underappreciated cause of epilepsy.
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Anomalías Múltiples/genética , Discapacidades del Desarrollo/genética , Epilepsia/genética , Hipotonía Muscular/genética , Mutación/genética , Fosfotransferasas/genética , Convulsiones/genética , Anomalías Múltiples/patología , Adolescente , Adulto , Niño , Preescolar , Discapacidades del Desarrollo/patología , Epilepsia/congénito , Epilepsia/patología , Femenino , Estudios de Asociación Genética , Genotipo , Humanos , Lactante , Masculino , Hipotonía Muscular/congénito , Hipotonía Muscular/patología , Linaje , Fenotipo , Pronóstico , Convulsiones/congénito , Convulsiones/patología , Síndrome , Adulto JovenRESUMEN
INTRODUCTION: Low back pain (LBP) is the leading global cause of disability. Patients with moderate to severe LBP who respond positively to a diagnostic medial nerve branch block can be offered radiofrequency denervation (RFD). However, high-quality evidence on the effectiveness of RFD is lacking. METHODS AND ANALYSIS: RADICAL (RADIofrequenCy denervAtion for Low back pain) is a double-blind, parallel-group, superiority randomised controlled trial. A total of 250 adults listed for RFD will be recruited from approximately 20 National Health Service (NHS) pain and spinal clinics. Recruitment processes will be optimised through qualitative research during a 12-month internal pilot phase. Participants will be randomised in theatre using a 1:1 allocation ratio to RFD or placebo. RFD technique will follow best practice guidelines developed for the trial. Placebo RFD will follow the same protocol, but the electrode tip temperature will not be raised. Participants who do not experience a clinically meaningful improvement in pain 3 months after randomisation will be offered the alternative intervention to the one provided at the outset without disclosing the original allocation. The primary clinical outcome will be pain severity, measured using a pain Numeric Rating Scale, at 3 months after randomisation. Secondary outcomes will be assessed up to 2 years after randomisation and include disability, health-related quality of life, psychological distress, time to pain recovery, satisfaction, adverse events, work outcomes and healthcare utilisation. The primary statistical analyses will be by intention to treat and will follow a prespecified analysis plan. The primary economic evaluation will take an NHS and social services perspective and estimate the discounted cost per quality-adjusted life-year and incremental net benefit of RFD over the 2-year follow-up period. ETHICS AND DISSEMINATION: Ethics approval was obtained from the London-Fulham Research Ethics Committee (21/LO/0471). Results will be disseminated in open-access publications and plain language summaries. TRIAL REGISTRATION NUMBER: ISRCTN16473239.
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Análisis Costo-Beneficio , Desnervación , Dolor de la Región Lumbar , Humanos , Dolor de la Región Lumbar/terapia , Dolor de la Región Lumbar/cirugía , Dolor de la Región Lumbar/economía , Método Doble Ciego , Desnervación/métodos , Desnervación/economía , Dimensión del Dolor , Dolor Crónico/terapia , Dolor Crónico/cirugía , Calidad de Vida , Resultado del Tratamiento , AdultoRESUMEN
Psychotic disorders are highly heterogeneous. Understanding relationships between symptoms will be relevant to their underlying pathophysiology. We apply dimensionality-reduction methods across two unique samples to characterize the patterns of symptom organization. We analyzed publicly-available data from 153 participants diagnosed with schizophrenia or schizoaffective disorder (fBIRN Data Repository and the Consortium for Neuropsychiatric Phenomics), as well as 636 first-episode psychosis (FEP) participants from the Prevention and Early Intervention Program for Psychosis (PEPP-Montreal). In all participants, the Scale for the Assessment of Positive Symptoms (SAPS) and Scale for the Assessment of Negative Symptoms (SANS) were collected. Multidimensional scaling (MDS) combined with cluster analysis was applied to SAPS and SANS scores across these two groups of participants. MDS revealed relationships between items of SAPS and SANS. Our application of cluster analysis to these results identified: 1 cluster of disorganization symptoms, 2 clusters of hallucinations/delusions, and 2 SANS clusters (asocial and apathy, speech and affect). Those reality distortion items which were furthest from auditory hallucinations had very weak to no relationship with hallucination severity. Despite being at an earlier stage of illness, symptoms in FEP presentations were similarly organized. While hallucinations and delusions commonly co-occur, we found that their specific themes and content sometimes travel together and sometimes do not. This has important implications, not only for treatment, but also for research-particularly efforts to understand the neurocomputational and pathophysiological mechanism underlying delusions and hallucinations.
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Trastornos Psicóticos , Esquizofrenia , Humanos , Deluciones/diagnóstico , Trastornos Psicóticos/psicología , Esquizofrenia/diagnóstico , Esquizofrenia/complicaciones , Alucinaciones/psicologíaRESUMEN
INTRODUCTION: Lung cancer is the most common cause of cancer death worldwide and most patients present with extensive disease. One-year survival is improving but remains low (37%) despite novel systemic anti-cancer treatments forming the current standard of care. Although new therapies improve survival, most patients have residual disease after treatment, and little is known on how best to manage it. Therefore, residual disease management varies across the UK, with some patients receiving only maintenance systemic anti-cancer treatment while others receive local consolidative treatment (LCT), alongside maintenance systemic anti-cancer treatment. LCT can be a combination of surgery, radiotherapy and/or ablation to remove all remaining cancer within the lung and throughout the body. This is intensive, expensive and impacts quality of life, but we do not know if it results in better survival, nor the extent of impact on quality of life and what the cost might be for healthcare providers. The RAMON study (RAdical Management Of Advanced Non-small cell lung cancer) will evaluate the acceptability, effectiveness and cost-effectiveness of LCT versus no LCT after first-line systemic treatment for advanced lung cancer. METHODS AND ANALYSIS: RAMON is a pragmatic open multicentre, parallel group, superiority randomised controlled trial. We aim to recruit 244 patients aged 18 years and over with advanced non-small-cell lung cancer from 40 UK NHS hospitals. Participants will be randomised in a 1:1 ratio to receive LCT alongside maintenance treatment, or maintenance treatment alone. LCT will be tailored to each patient's specific disease sites. Participants will be followed up for a minimum of 2 years. The primary outcome is overall survival from randomisation. ETHICS AND DISSEMINATION: The West of Scotland Research Ethics Committee (22/WS/0121) gave ethical approval in August 2022 and the Health Research Authority in September 2022. Participants will provide written informed consent before participating in the study. Findings will be presented at international meetings, in peer-reviewed publications, through patient organisations and notifications to patients. TRIAL REGISTRATION NUMBER: ISRCTN11613852.
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Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Adolescente , Adulto , Humanos , Carcinoma de Pulmón de Células no Pequeñas/terapia , Terapia Combinada , Pulmón , Neoplasias Pulmonares/terapia , Estudios Multicéntricos como Asunto , Calidad de Vida , Ensayos Clínicos Controlados Aleatorios como AsuntoRESUMEN
RATIONALE: While neural correlates of hallucinations are known, the mechanisms have remained elusive. Mechanistic insight is more practicable in animal models, in which causal relationships can be established. Recent work developing animal models of hallucination susceptibility has focused on the genesis of perceptual expectations and perceptual decision-making. Both processes are encompassed within mediated learning, which involves inducing a strong perceptual expectation via associative learning, retrieving that memory representation, and deciding whether this internally generated percept is predictive of an external outcome. Mediated learning in rodents is sensitive to many psychotomimetic manipulations. However, we do not know if these manipulations selectively alter learning of perceptual expectations versus their retrieval because of their presence throughout all task phases. OBJECTIVES: Here, we used mediated learning to study the targeted effect of a psychotomimetic agent on the retrieval of perceptual expectation. METHODS: We administered (R,S)-ketamine to rats selectively during the devaluation phase of a mediated learning task, when the representation of the expected cue is retrieved, to test the hypothesis that internally generated perceptual experiences underlie this altered mediated learning. RESULTS: We found that ketamine increased only mediated learning at a moderate dose in rats, but impaired direct learning at the high dose. CONCLUSIONS: These results suggest that ketamine can augment retrieval of perceptual expectations and thus this may be how it induces hallucination-like experiences in humans. More broadly, mediated learning may unite the conditioning, perceptual decision-making, and even reality monitoring accounts of psychosis in a manner that translates across species.
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Ketamina , Trastornos Psicóticos , Animales , Alucinaciones , Humanos , Ketamina/farmacología , Aprendizaje , Motivación , RatasRESUMEN
Ketamine is an uncompetitive N-methyl-d-aspartate (NMDA) glutamate receptor antagonist. It induces effects in healthy individuals that mimic symptoms associated with schizophrenia. We sought to root these experiences in altered brain function, specifically aberrant resting state functional connectivity (rsfMRI). In the present study, we acquired rsfMRI data under ketamine and placebo in a between-subjects design and analyzed seed-based measures of rsfMRI using large-scale networks, dorsolateral prefrontal cortex (DLPFC) and sub-nuclei of the thalamus. We found ketamine-induced alterations in rsfMRI connectivity similar to those seen in patients with schizophrenia, some changes that may be more comparable to early stages of schizophrenia, and other connectivity signatures seen in patients that ketamine did not recreate. We do not find any circuits from our regions of interest that correlates with positive symptoms of schizophrenia in our sample, although we find that DLPFC connectivity with ACC does correlate with a mood measure. These results provide support for ketamine's use as a model of certain biomarkers of schizophrenia, particularly for early or at-risk patients.
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Encéfalo/diagnóstico por imagen , Antagonistas de Aminoácidos Excitadores/efectos adversos , Ketamina/efectos adversos , Red Nerviosa/diagnóstico por imagen , Esquizofrenia/inducido químicamente , Esquizofrenia/diagnóstico por imagen , Adolescente , Adulto , Encéfalo/efectos de los fármacos , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Red Nerviosa/efectos de los fármacos , Adulto JovenRESUMEN
The mismatch negativity (MMN) is an event-related potential that is consistently attenuated in people with schizophrenia. Within the predictive coding model of psychosis, MMN impairment is thought to reflect the same prediction failures that are also thought to underlie the development and crystallization of delusions and hallucinations. However, the true relationship between symptom severity and MMN impairment across studies has not yet been established. The present meta-analysis used meta-regressions to examine the relationship between MMN impairment (quantified as Hedges' g) and PANSS positive and negative symptom totals across 62 and 68 samples, respectively. Furthermore, we examined the relationship between MMN impairment and group differences in educational achievement (n = 47 samples), cognitive ability (n = 36 samples), and age (n = 86 samples). Overall, we found no significant associations between MMN impairment and symptom severity (p's > 0.50); however, we did observe a trend-level association between MMN impairment and lower education (p = 0.07) and a significant association with older age (p < 0.01) in the schizophrenia patient group. Taken together, these results challenge a simple predictive coding model of psychosis, and suggest that MMN impairment may be more closely associated with premorbid functioning than with the expression of psychotic symptoms.
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BACKGROUND AND OBJECTIVES: Joubert syndrome is a genetically heterogeneous ciliopathy associated with >30 genes. The characteristics of kidney disease and genotype-phenotype correlations have not been evaluated in a large cohort at a single center. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: We evaluated 97 individuals with Joubert syndrome at the National Institutes of Health Clinical Center using abdominal ultrasonography, blood and urine chemistries, and DNA sequencing. RESULTS: Patients were ages 0.6-36 years old (mean of 9.0±7.6 years old); 41 were female. Mutations were identified in 19 genes in 92 patients; two thirds of the mutations resided in six genes: TMEM67, C5orf42, CC2D2A, CEP290, AHI1, and KIAA0586. Kidney disease was detected in 30%, most commonly in association with the following genes: CEP290 (six of six), TMEM67 (11 of 22), and AHI1 (three of six). No kidney disease was identified in patients with mutations in C5orf42 (zero of 15) or KIAA0586 (zero of six). Prenatal ultrasonography of kidneys was normal in 72% of patients with kidney disease. Specific types of kidney disease included nephronophthisis (31%), an overlap phenotype of autosomal recessive polycystic kidney disease/nephronophthisis (35%), unilateral multicystic dysplastic kidney (10%), and indeterminate-type cystic kidney disease (24%). Early-onset hypertension occurred in 24% of patients with kidney disease. Age at ESRD (n=13) ranged from 6 to 24 years old (mean of 11.3±4.8 years old). CONCLUSIONS: Kidney disease occurs in up to one third of patients with Joubert syndrome, most commonly in those with mutations in CEP290, TMEM67, and AHI1. Patients with mutations in C5orf42 or KIAA0586 are less likely to develop kidney disease. Prenatal ultrasonography is a poor predictor of kidney involvement in Joubert syndrome. Unilateral multicystic dysplastic kidney and autosomal recessive polycystic kidney disease-like enlarged kidneys with early-onset hypertension can be part of the Joubert syndrome kidney phenotype.
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Anomalías Múltiples/genética , Anomalías Múltiples/metabolismo , Cerebelo/anomalías , Anomalías del Ojo/genética , Anomalías del Ojo/metabolismo , Enfermedades Renales Quísticas/congénito , Fallo Renal Crónico/genética , Retina/anomalías , Anomalías Múltiples/diagnóstico por imagen , Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas Adaptadoras del Transporte Vesicular , Adolescente , Adulto , Edad de Inicio , Antígenos de Neoplasias/genética , Proteínas de Ciclo Celular/genética , Cerebelo/diagnóstico por imagen , Cerebelo/metabolismo , Niño , Preescolar , Proteínas del Citoesqueleto , Anomalías del Ojo/complicaciones , Anomalías del Ojo/diagnóstico por imagen , Femenino , Genotipo , Humanos , Lactante , Enfermedades Renales Quísticas/complicaciones , Enfermedades Renales Quísticas/diagnóstico por imagen , Enfermedades Renales Quísticas/genética , Enfermedades Renales Quísticas/metabolismo , Fallo Renal Crónico/etiología , Imagen por Resonancia Magnética , Masculino , Proteínas de la Membrana/genética , Riñón Displástico Multiquístico/complicaciones , Riñón Displástico Multiquístico/diagnóstico por imagen , Riñón Displástico Multiquístico/genética , Mutación , Proteínas de Neoplasias/genética , Fenotipo , Riñón Poliquístico Autosómico Recesivo/complicaciones , Riñón Poliquístico Autosómico Recesivo/diagnóstico por imagen , Riñón Poliquístico Autosómico Recesivo/genética , Estudios Prospectivos , Proteínas/genética , Retina/diagnóstico por imagen , Retina/metabolismo , Ultrasonografía Prenatal , Adulto JovenRESUMEN
Elucidating the function of highly conserved regulatory sequences is a significant challenge in genomics today. Certain intragenic highly conserved elements have been associated with regulating levels of core components of the spliceosome and alternative splicing of downstream genes. Here we identify mutations in one such element, a regulatory alternative exon of SNRPB as the cause of cerebro-costo-mandibular syndrome. This exon contains a premature termination codon that triggers nonsense-mediated mRNA decay when included in the transcript. These mutations cause increased inclusion of the alternative exon and decreased overall expression of SNRPB. We provide evidence for the functional importance of this conserved intragenic element in the regulation of alternative splicing and development, and suggest that the evolution of such a regulatory mechanism has contributed to the complexity of mammalian development.