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Alpha-tubulin 4A encoding gene (TUBA4A) has been associated with familial amyotrophic lateral sclerosis (fALS) and fronto-temporal dementia (FTD), based on identification of likely pathogenic variants in patients from distinct ALS and FTD cohorts. By screening a multicentric French cohort of 448 unrelated probands presenting with cerebellar ataxia, we identified ultra-rare TUBA4A missense variants, all being absent from public databases and predicted pathogenic by multiple in-silico tools. In addition, gene burden analyses in the 100,000 genomes project (100KGP) showed enrichment of TUBA4A rare variants in the inherited ataxia group compared to controls (OR: 57.0847 [10.2- 576.7]; p = 4.02 x10-07). Altogether, we report 12 patients presenting with spasticity and/or cerebellar ataxia and harboring a predicted pathogenic TUBA4A missense mutation, including 5 confirmed de novo cases and a mutation previously reported in a large family presenting with spastic ataxia. Cultured fibroblasts from 3 patients harboring distinct TUBA4A missense showed significant alterations in microtubule organisation and dynamics, providing insight of TUBA4A variants pathogenicity. Our data confirm the identification of a hereditary spastic ataxia disease gene with variable age of onset, expanding the clinical spectrum of TUBA4A associated phenotypes.
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Solve-RD is a pan-European rare disease (RD) research program that aims to identify disease-causing genetic variants in previously undiagnosed RD families. We utilised 10-fold coverage HiFi long-read sequencing (LRS) for detecting causative structural variants (SVs), single nucleotide variants (SNVs), insertion-deletions (InDels), and short tandem repeat (STR) expansions in extensively studied RD families without clear molecular diagnoses. Our cohort includes 293 individuals from 114 genetically undiagnosed RD families selected by European Rare Disease Network (ERN) experts. Of these, 21 families were affected by so-called 'unsolvable' syndromes for which genetic causes remain unknown, and 93 families with at least one individual affected by a rare neurological, neuromuscular, or epilepsy disorder without genetic diagnosis despite extensive prior testing. Clinical interpretation and orthogonal validation of variants in known disease genes yielded thirteen novel genetic diagnoses due to de novo and rare inherited SNVs, InDels, SVs, and STR expansions. In an additional four families, we identified a candidate disease-causing SV affecting several genes including an MCF2 / FGF13 fusion and PSMA3 deletion. However, no common genetic cause was identified in any of the 'unsolvable' syndromes. Taken together, we found (likely) disease-causing genetic variants in 13.0% of previously unsolved families and additional candidate disease-causing SVs in another 4.3% of these families. In conclusion, our results demonstrate the added value of HiFi long-read genome sequencing in undiagnosed rare diseases.
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Primary familial brain calcification (PFBC) is characterized by calcium deposition in the brain, causing progressive movement disorders, psychiatric symptoms, and cognitive decline. PFBC is a heterogeneous disorder currently linked to variants in six different genes, but most patients remain genetically undiagnosed. Here, we identify biallelic NAA60 variants in ten individuals from seven families with autosomal recessive PFBC. The NAA60 variants lead to loss-of-function with lack of protein N-terminal (Nt)-acetylation activity. We show that the phosphate importer SLC20A2 is a substrate of NAA60 in vitro. In cells, loss of NAA60 caused reduced surface levels of SLC20A2 and a reduction in extracellular phosphate uptake. This study establishes NAA60 as a causal gene for PFBC, provides a possible biochemical explanation of its disease-causing mechanisms and underscores NAA60-mediated Nt-acetylation of transmembrane proteins as a fundamental process for healthy neurobiological functioning.
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Encefalopatías , Humanos , Acetilación , Encéfalo/diagnóstico por imagen , Encéfalo/metabolismo , Encefalopatías/genética , Patrón de Herencia , Mutación , Fosfatos/metabolismo , Proteínas Cotransportadoras de Sodio-Fosfato de Tipo III/metabolismoRESUMEN
Neuromuscular diseases (NMDs) affect â¼15 million people globally. In high income settings DNA-based diagnosis has transformed care pathways and led to gene-specific therapies. However, most affected families are in low-to-middle income countries (LMICs) with limited access to DNA-based diagnosis. Most (86%) published genetic data is derived from European ancestry. This marked genetic data inequality hampers understanding of genetic diversity and hinders accurate genetic diagnosis in all income settings. We developed a cloud-based transcontinental partnership to build diverse, deeply-phenotyped and genetically characterized cohorts to improve genetic architecture knowledge, and potentially advance diagnosis and clinical management. We connected 18 centres in Brazil, India, South Africa, Turkey, Zambia, Netherlands and the UK. We co-developed a cloud-based data solution and trained 17 international neurology fellows in clinical genomic data interpretation. Single gene and whole exome data were analysed via a bespoke bioinformatics pipeline and reviewed alongside clinical and phenotypic data in global webinars to inform genetic outcome decisions. We recruited 6001 participants in the first 43 months. Initial genetic analyses 'solved' or 'possibly solved' â¼56% probands overall. In-depth genetic data review of the four commonest clinical categories (limb girdle muscular dystrophy, inherited peripheral neuropathies, congenital myopathy/muscular dystrophies and Duchenne/Becker muscular dystrophy) delivered a â¼59% 'solved' and â¼13% 'possibly solved' outcome. Almost 29% of disease causing variants were novel, increasing diverse pathogenic variant knowledge. Unsolved participants represent a new discovery cohort. The dataset provides a large resource from under-represented populations for genetic and translational research. In conclusion, we established a remote transcontinental partnership to assess genetic architecture of NMDs across diverse populations. It supported DNA-based diagnosis, potentially enabling genetic counselling, care pathways and eligibility for gene-specific trials. Similar virtual partnerships could be adopted by other areas of global genomic neurological practice to reduce genetic data inequality and benefit patients globally.
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Distrofia Muscular de Cinturas , Distrofias Musculares , Enfermedades Neuromusculares , Enfermedades del Sistema Nervioso Periférico , Humanos , Enfermedades Neuromusculares/genética , Distrofia Muscular de Cinturas/diagnóstico , ADNRESUMEN
PURPOSE: Nonerythrocytic αII-spectrin (SPTAN1) variants have been previously associated with intellectual disability and epilepsy. We conducted this study to delineate the phenotypic spectrum of SPTAN1 variants. METHODS: We carried out SPTAN1 gene enrichment analysis in the rare disease component of the 100,000 Genomes Project and screened 100,000 Genomes Project, DECIPHER database, and GeneMatcher to identify individuals with SPTAN1 variants. Functional studies were performed on fibroblasts from 2 patients. RESULTS: Statistically significant enrichment of rare (minor allele frequency < 1 × 10-5) probably damaging SPTAN1 variants was identified in families with hereditary ataxia (HA) or hereditary spastic paraplegia (HSP) (12/1142 cases vs 52/23,847 controls, p = 2.8 × 10-5). We identified 31 individuals carrying SPTAN1 heterozygous variants or deletions. A total of 10 patients presented with pure or complex HSP/HA. The remaining 21 patients had developmental delay and seizures. Irregular αII-spectrin aggregation was noted in fibroblasts derived from 2 patients with p.(Arg19Trp) and p.(Glu2207del) variants. CONCLUSION: We found that SPTAN1 is a genetic cause of neurodevelopmental disorder, which we classified into 3 distinct subgroups. The first comprises developmental epileptic encephalopathy. The second group exhibits milder phenotypes of developmental delay with or without seizures. The final group accounts for patients with pure or complex HSP/HA.
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Epilepsia , Paraplejía Espástica Hereditaria , Humanos , Espectrina/genética , Mutación , Epilepsia/genética , Fenotipo , Ataxia , Paraplejía Espástica Hereditaria/genética , Convulsiones , Paraplejía , LinajeRESUMEN
To discover rare disease-gene associations, we developed a gene burden analytical framework and applied it to rare, protein-coding variants from whole genome sequencing of 35,008 cases with rare diseases and their family members recruited to the 100,000 Genomes Project (100KGP). Following in silico triaging of the results, 88 novel associations were identified including 38 with existing experimental evidence. We have published the confirmation of one of these associations, hereditary ataxia with UCHL1 , and independent confirmatory evidence has recently been published for four more. We highlight a further seven compelling associations: hypertrophic cardiomyopathy with DYSF and SLC4A3 where both genes show high/specific heart expression and existing associations to skeletal dystrophies or short QT syndrome respectively; monogenic diabetes with UNC13A with a known role in the regulation of ß cells and a mouse model with impaired glucose tolerance; epilepsy with KCNQ1 where a mouse model shows seizures and the existing long QT syndrome association may be linked; early onset Parkinson's disease with RYR1 with existing links to tremor pathophysiology and a mouse model with neurological phenotypes; anterior segment ocular abnormalities associated with POMK showing expression in corneal cells and with a zebrafish model with developmental ocular abnormalities; and cystic kidney disease with COL4A3 showing high renal expression and prior evidence for a digenic or modifying role in renal disease. Confirmation of all 88 associations would lead to potential diagnoses in 456 molecularly undiagnosed cases within the 100KGP, as well as other rare disease patients worldwide, highlighting the clinical impact of a large-scale statistical approach to rare disease gene discovery.
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PPFIBP1 encodes for the liprin-ß1 protein, which has been shown to play a role in neuronal outgrowth and synapse formation in Drosophila melanogaster. By exome and genome sequencing, we detected nine ultra-rare homozygous loss-of-function variants in 16 individuals from 12 unrelated families. The individuals presented with moderate to profound developmental delay, often refractory early-onset epilepsy, and progressive microcephaly. Further common clinical findings included muscular hyper- and hypotonia, spasticity, failure to thrive and short stature, feeding difficulties, impaired vision, and congenital heart defects. Neuroimaging revealed abnormalities of brain morphology with leukoencephalopathy, ventriculomegaly, cortical abnormalities, and intracranial periventricular calcifications as major features. In a fetus with intracranial calcifications, we identified a rare homozygous missense variant that by structural analysis was predicted to disturb the topology of the SAM domain region that is essential for protein-protein interaction. For further insight into the effects of PPFIBP1 loss of function, we performed automated behavioral phenotyping of a Caenorhabditis elegans PPFIBP1/hlb-1 knockout model, which revealed defects in spontaneous and light-induced behavior and confirmed resistance to the acetylcholinesterase inhibitor aldicarb, suggesting a defect in the neuronal presynaptic zone. In conclusion, we establish bi-allelic loss-of-function variants in PPFIBP1 as a cause of an autosomal recessive severe neurodevelopmental disorder with early-onset epilepsy, microcephaly, and periventricular calcifications.
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Epilepsia , Microcefalia , Malformaciones del Sistema Nervioso , Trastornos del Neurodesarrollo , Acetilcolinesterasa/genética , Animales , Drosophila melanogaster/genética , Epilepsia/genética , Pérdida de Heterocigocidad , Microcefalia/genética , Trastornos del Neurodesarrollo/genética , LinajeRESUMEN
Background: Cancer testis antigens (CTA) are normally expressed in immune privileged tissues such as the testis. They are considered tumor-associated antigens because they are specifically expressed in different cancers. Their distinct nature rendered them appealing targets for cancer diagnosis, prognosis. and immunotherapy. We aimed to identify the association of two CTA genes with colon cancer (CC) in a cohort of Egyptian patients. Methods: We measured the relative gene expression levels of two CTAs: SPAG9 and FBXO39 in colonic tumor tissue and adjacent normal-appearing mucosa in 50 newly diagnosed colon cancer patients by real-time reverse transcription polymerase chain reaction. Gene expression was also studied in relation to demographic and pathological criteria. Results: SPAG9 and FBXO39 were overexpressed in 22% and 40% of cases, respectively. Overexpression of both genes was evident in 14% of cases. We report the significant expression of FBXO39 (P < 0.01) in tumor tissue compared to normal tissue. SPAG9 was significantly increased in large sized tumors compared to smaller sized tumors. Otherwise, there was no significant association between gene expression and the evaluated clinicopathological features (P > 0.05). Conclusions: SPAG9 and FBXO39 are possible CC diagnostic biomarkers. Further studies are warranted to validate our findings.
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Proteínas Adaptadoras Transductoras de Señales , Neoplasias del Colon , Proteínas F-Box , Humanos , Proteínas Adaptadoras Transductoras de Señales/genética , Antígenos de Neoplasias/genética , Biomarcadores de Tumor/genética , Neoplasias del Colon/genética , Proteínas F-Box/genética , PronósticoRESUMEN
OBJECTIVE: The study aimed to delineate the gene expression profile of LGR5, HES1 and ATOH1 in young Egyptian rectal cancer (RC) patients and investigate the correlation between expression profiles and clinical outcome. METHODS: The study was conducted on 30 young Egyptian RC patients. Expression study of LGR5, HES1 and ATOH1 were performed by quantitative PCR (QPCR) based on comparative Cq method after normalization to adjacent non tumor tissues and ACTB as a reference gene. Patients were followed up for assessment of response to neoadjuvant chemoradiotherapy (CRT) based on revised RECIST1.1. RESULT: The study detected overexpression of LGR5 and HES1 and down-regulation of ATOH1 in human RC tissues compared to non- tumor tissues. High expression of LGR5 was correlated with more depth of tumor invasion, lymph node (LN) metastasis, advanced cTNM stage and mesorectal fascia (MRF) involvement. More prominently, high LGR5 expression level was associated with poor response to CRT. LGR5 was suggested as unfavorable prognostic biomarker for RC. Conversely, HES1 and ATOH1 expression did not show significant association with most of the studied clinical criteria nor response to CRT. Still, HES1 and ATOH1 were significantly and inversely associated with presence of mucinous component. CONCLUSION: High LGR5 expression is indicative of poor prognosis among young Egyptian RC patients and is proposed as a predictive marker of resistance to neoadjuvant CRT. However, HES1 and ATOH1 expressions were not prognostic nor predictive of response to CRT. Overall, LGR5, HES1 and ATOH1 gene expression patterns among young onset RC patients, are in line with patterns encountered in older age groups.
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Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Expresión Génica , Receptores Acoplados a Proteínas G/genética , Neoplasias del Recto/genética , Factor de Transcripción HES-1/genética , Adulto , Egipto , Femenino , Humanos , Masculino , Terapia Neoadyuvante , Pronóstico , Neoplasias del Recto/tratamiento farmacológico , Adulto JovenRESUMEN
BACKGROUND: Hepatocellular carcinoma is a major health problem worldwide especially in Egypt. It accounts for the fifth common cancer and the second cause of death among different cancers. This study investigated the efficacy and molecular mechanism of Nisin and/or Thioridazine as anticancer treatment on human liver cancer HepG2 cell line. METHODS: Nisin and Thioridazine were applied for 24 h on human liver cancer cell line (HepG2). 3-(4, 5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was done to assess the cytotoxicity of Nisin and Thioridazine. Quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) was used for the assessment of PI3K, AKT, SIRT-1, and NRF2 expression in the treated cell line. The protein level of reactive oxygen species (ROS) and vascular endothelial growth factor (VEGF) was measured in the collected media by ELISA technique. Western blot analysis was done for, tAKT, pAKT, tPI3K, and pPI3K. RESULTS: Cell proliferation results showed that compared with the untreated cancer, Nisin and/or Thioridazine treated groups had decreased cell proliferation (p value< 0.0001). Nisin and/or Thioridazine decreased PI3K/AKT mRNA and protein expression in hepatocellular carcinoma cells (HCC). Also Nisin and/or Thioridazine decreased anti-oxidative SIRT1/NRF2 mRNA expression. ROS level highly increased with Nisin and/or Thioridazine treatment in contrast to VEGF protein level which was highly decreased. CONCLUSION: These results introduce Nisin and Thioridazine as new therapeutic lines in HCC.
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Joubert syndrome (JBTS) is a recessive neurodevelopmental ciliopathy characterized by a pathognomonic hindbrain malformation. All known JBTS genes encode proteins involved in the structure or function of primary cilia, ubiquitous antenna-like organelles essential for cellular signal transduction. Here, we used the recently identified JBTS-associated protein armadillo repeat motif-containing 9 (ARMC9) in tandem-affinity purification and yeast 2-hybrid screens to identify a ciliary module whose dysfunction underlies JBTS. In addition to the known JBTS-associated proteins CEP104 and CSPP1, we identified coiled-coil domain containing 66 (CCDC66) and TOG array regulator of axonemal microtubules 1 (TOGARAM1) as ARMC9 interaction partners. We found that TOGARAM1 variants cause JBTS and disrupt TOGARAM1 interaction with ARMC9. Using a combination of protein interaction analyses, characterization of patient-derived fibroblasts, and analysis of CRISPR/Cas9-engineered zebrafish and hTERT-RPE1 cells, we demonstrated that dysfunction of ARMC9 or TOGARAM1 resulted in short cilia with decreased axonemal acetylation and polyglutamylation, but relatively intact transition zone function. Aberrant serum-induced ciliary resorption and cold-induced depolymerization in ARMC9 and TOGARAM1 patient cell lines suggest a role for this new JBTS-associated protein module in ciliary stability.
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Anomalías Múltiples , Proteínas del Dominio Armadillo , Cerebelo/anomalías , Cilios , Anomalías del Ojo , Enfermedades Renales Quísticas , Retina/anomalías , Proteínas de Pez Cebra , Pez Cebra , Anomalías Múltiples/genética , Anomalías Múltiples/metabolismo , Acetilación , Animales , Proteínas del Dominio Armadillo/genética , Proteínas del Dominio Armadillo/metabolismo , Sistemas CRISPR-Cas , Cerebelo/metabolismo , Cilios/genética , Cilios/metabolismo , Modelos Animales de Enfermedad , Anomalías del Ojo/genética , Anomalías del Ojo/metabolismo , Humanos , Enfermedades Renales Quísticas/genética , Enfermedades Renales Quísticas/metabolismo , Péptidos/genética , Péptidos/metabolismo , Retina/metabolismo , Pez Cebra/genética , Pez Cebra/metabolismo , Proteínas de Pez Cebra/genética , Proteínas de Pez Cebra/metabolismoRESUMEN
Developmental and epileptic encephalopathies are a heterogeneous group of early-onset epilepsy syndromes dramatically impairing neurodevelopment. Modern genomic technologies have revealed a number of monogenic origins and opened the door to therapeutic hopes. Here we describe a new syndromic developmental and epileptic encephalopathy caused by bi-allelic loss-of-function variants in GAD1, as presented by 11 patients from six independent consanguineous families. Seizure onset occurred in the first 2 months of life in all patients. All 10 patients, from whom early disease history was available, presented with seizure onset in the first month of life, mainly consisting of epileptic spasms or myoclonic seizures. Early EEG showed suppression-burst or pattern of burst attenuation or hypsarrhythmia if only recorded in the post-neonatal period. Eight patients had joint contractures and/or pes equinovarus. Seven patients presented a cleft palate and two also had an omphalocele, reproducing the phenotype of the knockout Gad1-/- mouse model. Four patients died before 4 years of age. GAD1 encodes the glutamate decarboxylase enzyme GAD67, a critical actor of the γ-aminobutyric acid (GABA) metabolism as it catalyses the decarboxylation of glutamic acid to form GABA. Our findings evoke a novel syndrome related to GAD67 deficiency, characterized by the unique association of developmental and epileptic encephalopathies, cleft palate, joint contractures and/or omphalocele.
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Síndromes Epilépticos/genética , Síndromes Epilépticos/patología , Síndromes Epilépticos/fisiopatología , Glutamato Descarboxilasa/genética , Anomalías Múltiples/genética , Femenino , Humanos , Recién Nacido , Masculino , Mutación , LinajeRESUMEN
Auriculocondylar syndrome (ARCND, MIM #614669, #602483, and #615706); also known as ''question-mark ear syndrome'' or ''dysgnathia complex'', is a rare craniofacial malformation of first and second branchial arches with a prevalence of <1/1,000,000. It is characterized by a distinctive auricular malformation (question mark ear (QME)) and highly variable mandibular anomalies. Variants found in PLCB4, GNAI3, and in EDN1 genes are responsible for >90% of tested ARCND patients. Whole exome sequencing in a multigenerational Egyptian kindred with high intrafamilial variability revealed a known heterozygous missense variant in PLCB4 (NM_000933.3:c.1862G>A:p.(Arg621His)). This report increases the number of molecularly characterized ARCND patients to 29 and emphasizes the highly variable clinical presentation within families.
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Enfermedades del Oído/genética , Oído/anomalías , Mutación , Fenotipo , Fosfolipasa C beta/genética , Adolescente , Adulto , Niño , Oído/patología , Enfermedades del Oído/patología , Endotelina-1/genética , Femenino , Subunidades alfa de la Proteína de Unión al GTP Gi-Go/genética , Humanos , Masculino , LinajeRESUMEN
PURPOSE: Ciliopathies are highly heterogeneous clinical disorders of the primary cilium. We aim to characterize a large cohort of ciliopathies phenotypically and molecularly. METHODS: Detailed phenotypic and genomic analysis of patients with ciliopathies, and functional characterization of novel candidate genes. RESULTS: In this study, we describe 125 families with ciliopathies and show that deleterious variants in previously reported genes, including cryptic splicing variants, account for 87% of cases. Additionally, we further support a number of previously reported candidate genes (BBIP1, MAPKBP1, PDE6D, and WDPCP), and propose nine novel candidate genes (CCDC67, CCDC96, CCDC172, CEP295, FAM166B, LRRC34, TMEM17, TTC6, and TTC23), three of which (LRRC34, TTC6, and TTC23) are supported by functional assays that we performed on available patient-derived fibroblasts. From a phenotypic perspective, we expand the phenomenon of allelism that characterizes ciliopathies by describing novel associations including WDR19-related Stargardt disease and SCLT1- and CEP164-related Bardet-Biedl syndrome. CONCLUSION: In this cohort of phenotypically and molecularly characterized ciliopathies, we draw important lessons that inform the clinical management and the diagnostics of this class of disorders as well as their basic biology.
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Síndrome de Bardet-Biedl , Ciliopatías , Alelos , Síndrome de Bardet-Biedl/genética , Cilios/genética , Ciliopatías/genética , Humanos , Canales de SodioRESUMEN
BACKGROUND: Primary ciliary dyskinesia (PCD), a genetically heterogeneous condition enriched in some consanguineous populations, results from recessive mutations affecting cilia biogenesis and motility. Currently, diagnosis requires multiple expert tests. METHODS: The diagnostic utility of multigene panel next-generation sequencing (NGS) was evaluated in 161 unrelated families from multiple population ancestries. RESULTS: Most (82%) families had affected individuals with biallelic or hemizygous (75%) or single (7%) pathogenic causal alleles in known PCD genes. Loss-of-function alleles dominate (73% frameshift, stop-gain, splice site), most (58%) being homozygous, even in non-consanguineous families. Although 57% (88) of the total 155 diagnostic disease variants were novel, recurrent mutations and mutated genes were detected. These differed markedly between white European (52% of families carry DNAH5 or DNAH11 mutations), Arab (42% of families carry CCDC39 or CCDC40 mutations) and South Asian (single LRRC6 or CCDC103 mutations carried in 36% of families) patients, revealing a striking genetic stratification according to population of origin in PCD. Genetics facilitated successful diagnosis of 81% of families with normal or inconclusive ultrastructure and 67% missing prior ultrastructure results. CONCLUSIONS: This study shows the added value of high-throughput targeted NGS in expediting PCD diagnosis. Therefore, there is potential significant patient benefit in wider and/or earlier implementation of genetic screening.
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Cilios/genética , Trastornos de la Motilidad Ciliar/genética , Pruebas Genéticas , Secuenciación de Nucleótidos de Alto Rendimiento , Alelos , Pueblo Asiatico/genética , Cilios/patología , Trastornos de la Motilidad Ciliar/diagnóstico , Trastornos de la Motilidad Ciliar/patología , Estudios de Cohortes , Etnicidad/genética , Femenino , Homocigoto , Humanos , Masculino , Mutación/genética , FenotipoRESUMEN
Primary ciliary dyskinesia (PCD) is a rare genetic disorder of motile cilia dysfunction generally inherited as an autosomal recessive disease. Genetic testing is increasingly considered an early step in the PCD diagnostic workflow. We used targeted panel next-generation sequencing (NGS) for genetic screening of 33 Egyptian families with clinically highly suspected PCD. All variants prioritized were Sanger confirmed in the affected individuals and correctly segregated within the family. Targeted NGS yielded a high diagnostic output (70%) with biallelic mutations identified in known PCD genes. Mutations were identified in 13 genes overall, with CCDC40 and CCDC39 the most frequently mutated genes among Egyptian patients. Most identified mutations were predicted null effect variants (79%) and not reported before (85%). This study reveals that the genetic landscape of PCD among Egyptians is highly heterogeneous, indicating that a targeted NGS approach covering multiple genes will provide a superior diagnostic yield compared to Sanger sequencing for genetic diagnosis. The high diagnostic output achieved here highlights the potential of placing genetic testing early within the diagnostic workflow for PCD, in particular in developing countries where other diagnostic tests can be less available.
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Trastornos de la Motilidad Ciliar/genética , Proteínas del Citoesqueleto/genética , Predisposición Genética a la Enfermedad , Proteínas/genética , Adolescente , Niño , Preescolar , Cilios/patología , Trastornos de la Motilidad Ciliar/epidemiología , Trastornos de la Motilidad Ciliar/patología , Egipto/epidemiología , Femenino , Pruebas Genéticas , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Lactante , Masculino , Mutación/genética , FenotipoRESUMEN
PURPOSE: In the present study, we investigated whether interleukin 1 beta (IL1B) promoter polymorphisms are associated with keratoconus in an Egyptian population and their association with disease severity. METHODS: A total of 95 Egyptian keratoconus patients and 126 Egyptian healthy controls were enrolled in the study. Two IL1B single nucleotide polymorphisms (SNPs) (rs1143627 and rs16944) were genotyped using Taqman real-time PCR to compare haplotype, genotype, and allele frequencies between cases and controls (primary outcome) and their association with disease severity (secondary outcome). RESULTS: Statistically significant association was observed for rs1143627 and rs16944; the T allele of rs1143627 and the G allele of rs16944 were associated with an increased risk of keratoconus (p < 0.001, odds ratio = 3.313, 4.770, respectively). The TT genotype of rs1143627 and the GG genotype of rs16944 were strongly associated with an increased risk of keratoconus (p < 0.001, odds ratio = 5.631, 11.478, respectively). The G allele of rs16944 was associated with an increased curvature of the flattest corneal meridian Kf in keratoconus (p = 0.041). The GG genotype of rs16944 was associated with an increased curvature of the flattest corneal meridian Kf, steepest corneal meridian Ks and average corneal curvature Kavg in keratoconus (p = 0.01, 0.046, 0.023, respectively). CONCLUSION: IL1B is suspected to play a crucial role, both in development and severity of keratoconus in Egyptian population.
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Lissencephaly is a severe brain malformation in which failure of neuronal migration results in agyria or pachygyria and in which the brain surface appears unusually smooth. It is often associated with microcephaly, profound intellectual disability, epilepsy, and impaired motor abilities. Twenty-two genes are associated with lissencephaly, accounting for approximately 80% of disease. Here we report on 12 individuals with a unique form of lissencephaly; these individuals come from eight unrelated families and have bi-allelic mutations in APC2, encoding adenomatous polyposis coli protein 2. Brain imaging studies demonstrate extensive posterior predominant lissencephaly, similar to PAFAH1B1-associated lissencephaly, as well as co-occurrence of subcortical heterotopia posterior to the caudate nuclei, "ribbon-like" heterotopia in the posterior frontal region, and dysplastic in-folding of the mesial occipital cortex. The established role of APC2 in integrating the actin and microtubule cytoskeletons to mediate cellular morphological changes suggests shared function with other lissencephaly-encoded cytoskeletal proteins such as α-N-catenin (CTNNA2) and platelet-activating factor acetylhydrolase 1b regulatory subunit 1 (PAFAH1B1, also known as LIS1). Our findings identify APC2 as a radiographically distinguishable recessive form of lissencephaly.
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Alelos , Lisencefalias Clásicas y Heterotopias Subcorticales en Banda/genética , Proteínas del Citoesqueleto/genética , Discapacidades del Desarrollo/genética , Lisencefalia/genética , Femenino , Humanos , Masculino , LinajeRESUMEN
AIM: To determine the possible association between polymorphisms of DNA repair genes, including XRCC1 Arg194Tryp, Arg280His, and Arg399Glu, APE1 Asp148Glu, and NEIL2 Arg257Leu, and the risk of developing hepatitis C virus (HCV)-related hepatocellular carcinoma (HCC). METHODS: A total of 264 subjects were recruited in this retrospective case-control study and were categorized into four groups: 88 control subjects (CR), 53 chronic hepatitis C patients (CHC), 36 liver cirrhotic patients (LC), and 87 HCC patients. The XRCC1 Arg194Tryp, Arg280His, and Arg399Glu polymorphisms were detected using PCR-RFLP, while real-time PCR was used to genotype APE1 Asp148Glu and NEIL2 Arg257Leu. RESULTS: Our data revealed that, compared with the healthy controls, for those subjects with the XRCC1 Arg194Trp genotype, the risk of developing CHC, LC, and HCC was increased by 6.66- (odds ratio (OR)â¯=â¯6.667; 95% confidence interval (CI)â¯=â¯3.244-13.701; Pâ¯>â¯0.01), 3.85- (ORâ¯=â¯3.852; 95% CIâ¯=â¯1.797-8.256; Pâ¯>â¯0.01), and 2.14-fold (ORâ¯=â¯2.14; 95% CIâ¯=â¯1.13-4.06; Pâ¯>â¯0.05), respectively. There was no association between the risk of HCC development and the XRCC1 Arg280His or XRCC1 Arg399Gln genotypes. Moreover, the analysis showed a lack of association between APE1 Asp148Glu and the risk of HCC development. The analysis of clinicopathological parameters showed that the HCC patients with the XRCC1 Arg280His polymorphism were 2.9 fold more likely to have hepatic lesions in both hepatic lobes (OR: 2.9; 95% CI: 1.15-7.29). Notably, in the HCC patients, the prevalence of the APE1 polymorphism in the males was four times higher than that in the females (ORâ¯=â¯4; 95% CIâ¯=â¯1.129-14.175; Pâ¯>â¯0.05). CONCLUSION: Our results indicate that the XRCC1 Arg194Trp polymorphism could be a risk factor for HCV-related HCC development in Egypt.