Considerations on a mutation in the NOTCH3 gene sparing a cysteine residue: a rare polymorphism rather than a CADASIL variant.
Ontology highlight
ABSTRACT:
SUBMITTER: Bersano A
PROVIDER: S-EPMC3861349 | biostudies-literature | 2012 Oct-Dec
REPOSITORIES: biostudies-literature
Publications
Considerations on a mutation in the NOTCH3 gene sparing a cysteine residue: a rare polymorphism rather than a CADASIL variant.
Bersano Anna A Ranieri Michela M Ciammola Andrea A Cinnante Claudia C Lanfranconi Silvia S Dotti Maria Teresa MT Candelise Livia L Baschirotto Cinzaia C Ghione Isabella I Ballabio Elena E Bresolin Nereo N Bassi Maria Teresa MT
Functional neurology 20121001 4
Some missense mutations and small deletions in the NOTCH3 gene, not involving cysteine residues, have been described in patients considered to be affected by paucisymptomatic CADASIL. However, the significance of such molecular variants is still unclear. We describe a 49-year-old woman with a CADASIL-like phenotype, carrying a novel cysteine-sparing mutation in exon 29 of the NOTCH3 gene, and discuss the possible pathogenetic role of this molecular variant. Even though atypical clinical and MRI ...[more]
Similar Datasets
Project description:Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is an adult onset cerebral small vessel disorder caused by the mutations of the neurogenic locus notch homolog protein 3 (NOTCH3) gene. The extracellular part of NOTCH3 is composed of 34 epidermal growth factor-like (EGF-like) repeat domains. Each EGF-like domain is rich of cysteine and glycine to produce three loops that are essential for high-affinity binding to its ligand. Nearly all reported CADASIL-associated mutations result in gain or loss of a cysteine residue within the EGF-like domains. Only a few cysteine-sparing NOTCH3 mutations have been documented in the patients with CADASIL to date. Here, we reported a Chinese CADASIL family with a cysteine-sparing NOTCH3 mutation. In this family, affected patients had dizziness, memory loss, gait instability, or hemiplegia. Brain magnetic resonance imaging (MRI) showed diffuse leukoencephalopathy with confluent signal abnormalities in the periventricular white matter, basal ganglia, and centrum semiovale bilaterally. By screening the entire coding region of NOTCH3, a novel missense mutation p.G149V (c.446G>T) was found. This mutation was not detected in 400 normal controls. Considering the critical position of glycine within the C-loop of EGF-like domain and its high conservation through evolution, p.G149V mutation could be a potential pathogenic cause for CADASIL.
| S-EPMC4123979 | biostudies-literature
Project description:AimsCADASIL, the most prevalent hereditary cerebral small vessel disease, is caused by cysteine-altering NOTCH3 variants (NOTCH3cys ) leading to vascular NOTCH3 protein aggregation. It has recently been shown that variants located in one of NOTCH3 protein epidermal growth-factor like repeat (EGFr) domains 1-6, are associated with a more severe phenotype than variants located in one of the EGFr domains 7-34. The underlying mechanism for this genotype-phenotype correlation is unknown. The aim of this study was to analyse whether NOTCH3cys variant position is associated with NOTCH3 protein aggregation load.MethodsWe quantified vascular NOTCH3 aggregation in skin biopsies (n = 25) and brain tissue (n = 7) of CADASIL patients with a NOTCH3cys EGFr 1-6 variant or a EGFr 7-34 variant, using NOTCH3 immunohistochemistry (NOTCH3 score) and ultrastructural analysis of granular osmiophilic material (GOM count). Disease severity was assessed by neuroimaging (lacune count and white matter hyperintensity volume) and disability (modified Rankin scale).ResultsPatients with NOTCH3cys EGFr 7-34 variants had lower NOTCH3 scores (P = 1.3·10-5 ) and lower GOM counts (P = 8.2·10-5 ) than patients with NOTCH3cys EGFr 1-6 variants in skin vessels. A similar trend was observed in brain vasculature. In the EGFr 7-34 group, NOTCH3 aggregation levels were associated with lacune count (P = 0.03) and white matter hyperintensity volume (P = 0.02), but not with disability.ConclusionsCADASIL patients with an EGFr 7-34 variant have significantly less vascular NOTCH3 aggregation than patients with an EGFr 1-6 variant. This may be one of the factors underlying the difference in disease severity between NOTCH3cys EGFr 7-34 and EGFr 1-6 variants.
| S-EPMC9291091 | biostudies-literature
Project description:Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is an inherited vascular dementia characterised by recurrent ischemic strokes in the deep white matter. Mutations in the gene encoding the cell surface receptor, Notch3, have been identified in CADASIL patients, and accumulation of the extracellular domain of Notch3 has been demonstrated in affected vessels. Almost all CADASIL mutations alter the number of cysteine residues in the epidermal growth factor (EGF)-like repeats in the extracellular domain of the protein.To understand the functional consequences of a recurrent CADASIL mutation on furin processing, cell surface expression, ligand binding, and activation of a downstream effector CBF1 by the Notch3 receptor.We expressed wild type and mutant Notch3 receptors in cultured cells and examined cell surface expression of the proteins. We also applied a new flow cytometry based approach to semi-quantitatively measure binding to three Notch ligands. Additionally, we used a well characterised co-culture system to examine ligand dependent activation of transcription from a CBF1-luciferase reporter construct.These studies revealed subtle abnormalities in furin processing of the mutant receptor, although both heterodimeric and full length receptors are present on the cell surface, are capable of interacting with soluble forms of three ligands, Delta1, Delta4, and Jagged1, and retain the ability to activate CBF1 in a ligand dependent manner.By comparison with other mutant forms of Notch3, these data indicate that individual CADASIL mutations can have disparate effects on Notch3 expression and function.
| S-EPMC1739793 | biostudies-other
Project description:BackgroundCerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is an inherited small vessel disease caused by mutations in NOTCH3 gene with remarkable phenotypic heterogeneity. Cases of CADASIL associated with homozygous NOTCH3 mutations are rare and subsequently understudied. In this study, we investigate the genetic and phenotypic features within patients of CADASIL with homozygous NOTCH3 mutations.Case presentationWe recruited two affected individuals with CADASIL from a mainland Chinese family. The proband (Patient 1), a 60-year-old male, presented with slow progressive gait instability, severe cognitive impairment, and emotional disorder for more than 2 years with a history of ischemic stroke and hypertension. His younger brother (Patient 2) presented with apparent gait difficulties, dysarthria as well as cognitive decline at 59 years old. Brain magnetic resonance imaging (MRI) showed diffused white matter lesions involving bilateral periventricular white matter, semioval center region, and anterior temporal lobes. Molecular genetic testing identified a homozygous variant, c.1759C > T (p.R587C), in NOTCH3 gene in both patients. Pathological analysis revealed granular osmiophilic material (GOM) deposits in small arterial walls of skin from the proband. The diagnosis of CADASIL was confirmed.ConclusionsOur cases of CADASIL with homozygous mutation c.1759C > T (p.R587C) in NOTCH3 share similar manifestation to the patients with heterozygous same mutation reported previously. Other than genetic factors, vascular risk factors or environmental factors might contribute to the phenotypic variation of CADASIL.
| S-EPMC7053106 | biostudies-literature
Project description:Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a rare hereditary stroke caused by mutations in NOTCH3 gene. We report the first case of CADASIL in an indigenous Rungus (Kadazan-Dusun) family in Kudat, Sabah, Malaysia confirmed by a R54C (c.160C>T, p.Arg54Cys) mutation in the NOTCH3. This mutation was previously reported in a Caucasian and two Korean cases of CADASIL. We recruited two generations of the affected Rungus family (n = 9) and found a missense mutation (c.160C>T) in exon 2 of NOTCH3 in three siblings. Two of the three siblings had severe white matter abnormalities in their brain MRI (Scheltens score 33 and 50 respectively), one of whom had a young stroke at the age of 38. The remaining sibling, however, did not show any clinical features of CADASIL and had only minimal changes in her brain MRI (Scheltens score 17). This further emphasized the phenotype variability among family members with the same mutation in CADASIL. This is the first reported family with CADASIL in Rungus subtribe of Kadazan-Dusun ethnicity with a known mutation at exon 2 of NOTCH3. The penetrance of this mutation was not complete during the course of this study.
| S-EPMC4535948 | biostudies-literature
Project description:ObjectiveTo determine the small vessel disease spectrum associated with cysteine-altering NOTCH3 variants in community-dwelling individuals by analyzing the clinical and neuroimaging features of UK Biobank participants harboring such variants.MethodsThe exome and genome sequencing datasets of the UK Biobank (n = 50,000) and cohorts of cognitively healthy elderly (n = 751) were queried for cysteine-altering NOTCH3 variants. Brain MRIs of individuals harboring such variants were scored according to Standards for Reporting Vascular Changes on Neuroimaging criteria, and clinical information was extracted with ICD-10 codes. Clinical and neuroimaging data were compared to age- and sex-matched UK Biobank controls and clinically diagnosed patients from the Dutch cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) registry.ResultsWe identified 108 individuals harboring a cysteine-altering NOTCH3 variant (2.2 of 1,000), of whom 75% have a variant that has previously been reported in CADASIL pedigrees. Almost all variants were located in 1 of the NOTCH3 protein epidermal growth factor-like repeat domains 7 to 34. White matter hyperintensity lesion load was higher in individuals with NOTCH3 variants than in controls (p = 0.006) but lower than in patients with CADASIL with the same variants (p < 0.001). Almost half of the 24 individuals with brain MRI had a Fazekas score of 0 or 1 up to age 70 years. There was no increased risk of stroke.ConclusionsAlthough community-dwelling individuals harboring a cysteine-altering NOTCH3 variant have a higher small vessel disease MRI burden than controls, almost half have no MRI abnormalities up to age 70 years. This shows that NOTCH3 cysteine altering variants are associated with an extremely broad phenotypic spectrum, ranging from CADASIL to nonpenetrance.
| S-EPMC7682826 | biostudies-literature
Project description:Notch3 is a member of the Notch family and its mutations are known to cause a hereditary human disorder called cerebral autosomal-dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL). However, the specific function and signaling cascade initiated by CADASIL mutants remain unknown. To gain further insight into mechanism of action of CADASIL mutants, the present study conducted several experiments on the effects of Notch3 mutants in multiple cell lines. The protein levels of Notch3, fibronectin, collagen, inducible nitric oxide synthase and DNA (cytosine-5)-methyltransferase 1 (DNMT1) were determined by western blotting. The mRNA levels of IL-1? and TNF-? were measured by reverse transcription semi-quantitative PCR and DNMT1 mRNA levels were determined by quantitative PCR. Trypan blue staining was used for proliferation analysis and wound healing assays were performed to determine cell migration capability. The present study reported that R90C and R169C Notch3 mutants, and wild-type Notch3 had different effects on several cell lines. In T/GHA-VSMC cells, following the transfection of the two mutants, collagen and fibronectin expression increased, whereas expression decreased in IMR-90 cells. In BV2 cells, the two mutants resulted in decreased nitric oxide and iNOS production. In HeLa cells, proliferation and migration increased significantly following the transfection of the two mutants, whereas in the MCF-7 and HCC1937 cell lines, cell proliferation and migration decreased. In addition, the two mutants suppressed the expression of DNMT1 in HeLa and IMR-90 cells. Overall, the present study provided novel insights that further explored the underlying mechanisms of CADASIL.
| S-EPMC7739825 | biostudies-literature
Project description:Genome-wide association studies (GWASs) have successfully uncovered thousands of robust associations between common variants and complex traits and diseases. Despite these successes, much of the heritability of these traits remains unexplained. Because low-frequency and rare variants are not tagged by conventional genome-wide genotyping arrays, they may represent an important and understudied component of complex trait genetics. In contrast to common variant GWASs, there are many different types of study designs, assays and analytic techniques that can be utilized for rare variant association studies (RVASs). In this review, we briefly present the different technologies available to identify rare genetic variants, including novel exome arrays. We also compare the different study designs for RVASs and argue that the best design will likely be phenotype-dependent. We discuss the main analytical issues relevant to RVASs, including the different statistical methods that can be used to test genetic associations with rare variants and the various bioinformatic approaches to predicting in silico biological functions for variants. Finally, we describe recent rare variant association findings, highlighting the unexpected conclusion that most rare variants have modest-to-small effect sizes on phenotypic variation. This observation has major implications for our understanding of the genetic architecture of complex traits in the context of the unexplained heritability challenge.
| S-EPMC4337325 | biostudies-literature
Project description:PURPOSE:CADASIL is a small-vessel disease caused by a cysteine-altering pathogenic variant in one of the 34 epidermal growth factor-like repeat (EGFr) domains of the NOTCH3 protein. We recently found that pathogenic variant in EGFr domains 7-34 have an unexpectedly high frequency in the general population (1:300). We hypothesized that EGFr 7-34 pathogenic variant more frequently cause a much milder phenotype, thereby explaining an important part of CADASIL disease variability. METHODS:Age at first stroke, survival and white matter hyperintensity volume were compared between 664 CADASIL patients with either a NOTCH3 EGFr 1-6 pathogenic variant or an EGFr 7-34 pathogenic variant. The frequencies of NOTCH3 EGFr 1-6 and EGFr 7-34 pathogenic variant were compared between individuals in the genome Aggregation Database and CADASIL patients. RESULTS:CADASIL patients with an EGFr 1-6 pathogenic variant have a 12-year earlier onset of stroke than those with an EGFr 7-34 pathogenic variant, lower survival, and higher white matter hyperintensity volumes. Among diagnosed CADASIL patients, 70% have an EGFr 1-6 pathogenic variant, whereas EGFr 7-34 pathogenic variant strongly predominate in the population. CONCLUSION:NOTCH3 pathogenic variant position is the most important determinant of CADASIL disease severity, with EGFr 7-34 pathogenic variant predisposing to a later onset of stroke and longer survival.
| S-EPMC6752295 | biostudies-literature
Project description:CADASIL is a vascular protein aggregation disorder caused by cysteine-altering NOTCH3 variants, leading to mid-adult-onset stroke and dementia. Here, we report individuals with a cysteine-altering NOTCH3 variant that induces exon 9 skipping, mimicking therapeutic NOTCH3 cysteine correction. The index came to our attention after a coincidental finding on a commercial screening MRI, revealing white matter hyperintensities. A heterozygous NOTCH3 c.1492G>T, p.Gly498Cys variant, was identified using a gene panel, which was also present in four first- and second-degree relatives. Although some degree of white matter hyperintensities was present on MRI in all family members with the NOTCH3 variant, the CADASIL phenotype was mild, as none had lacunes on MRI and there was no disability or cognitive impairment above the age of 60 years. RT-PCR and Sanger sequencing analysis on patient fibroblast RNA revealed that exon 9 was absent from the majority of NOTCH3 transcripts of the mutant allele, effectively excluding the mutation. NOTCH3 aggregation was assessed in skin biopsies using electron microscopy and immunohistochemistry and did not show granular osmiophilic material and only very mild NOTCH3 staining. For purposes of therapeutic translatability, we show that, in cell models, exon 9 exclusion can be obtained using antisense-mediated exon skipping and CRISPR/Cas9-mediated genome editing. In conclusion, this study provides the first in-human evidence that cysteine corrective NOTCH3 exon skipping is associated with less NOTCH3 aggregation and an attenuated phenotype, justifying further therapeutic development of NOTCH3 cysteine correction for CADASIL.
| S-EPMC7372551 | biostudies-literature