Cerebral Autosomal Dominant Arteriopathy With Subcortical Infarcts And Leukoencephalopathy Cases Research Articles

Early Diagnosis of Schizophrenia and Secondary Diagnose of Cerebral autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy: A Case Report

Background & Objective: Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy (CADASIL) is a rare disease with a prevalence estimation of, 5 per, 100,000 individuals. Besides, it can highly be misdiagnosed with other psychiatric disorders.
 Case Presentation: We report a case of CADASIL in a 32-year-old Asian female presenting with schizophrenia symptoms such as auditory hallucination ،loosening of associations، persecutory delusions، referential delusions، decreased function, and complex hepatic hallucinations that the patient had said sometimes someone has intercourse with me since 2 years ago. After brain Magnetic Resonance Imaging (MRI) and gene checking, she showed up with NOTCH3 gene, besides Brain Magnetic resonance imaging confirmed the presence of CADASIL. Supportive treatments have been done and two years of following up showed a significant increase in patient life quality
 Conclusion: This case report demonstrates the challenges of CADASIL diagnosis in a patient with schizophrenia symptoms. The diagnosis should be considered in patients with schizophrenia symptoms. Hence, there is a need for timely diagnosis and management of this disorder.

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) masquerading as CNS demyelination

BackgroundCADASIL is the most common single-gene disorder causing ischemic stroke. CADASIL has been linked to mutations in NOTCH3 gene, due to heterozygous missense mutations. The disease is of insidious onset, presenting with initial clinical features in third and fourth decade of life. However, it is now being increasingly acknowledged that individual clinical presentation, age, time of onset as well as disease severity are quite varied among patients with CADASIL most likely leading to under- or mis-diagnosis. The authors thereby report a genetically confirmed case of CADASIL with atypical clinical course and findings.Case presentationA 48-year-old woman presented with complaints of episodic headache, relapsing–remitting neurological illness, progressive cognitive impairment, and acute-onset loss of speech and ambulation. She was earlier being treated as a case of CNS demyelination for 10 years. On examination, vital parameters were within normal limits. Neurological examination revealed that the patient was drowsy, not verbalizing, not obeying commands, with movement of all four limbs on painful stimuli, hypertonia of all limbs, grade 3 + deep tendon reflexes, bilateral striatal toe and extensor plantar response. Magnetic resonance imaging of brain showed involvement of anterior temporal lobe and external capsule along with multiple acute infarcts. Cerebrospinal fluid analysis was found to be normal. Exome sequencing revealed heterozygous missense mutation in exon 2 of NOTCH3 gene. A definite diagnosis of CADASIL was made and patient was started on fluoxetine and aspirin, following which there was significant improvement over 4–6 weeks. Patient is able to carry out daily activities independently although continues to have mild persistent cognitive impairment with excessive talking and over familiarity.ConclusionsAs CADASIL has a relapsing and partially remitting course with frequently observed varied clinical presentation, patients may receive treatment for demyelination which may not be necessary. Hence, detailed family history along with knowledge of characteristic magnetic resonance imaging findings seen in CADASIL can help discern the diagnosis.

CADASIL and Cavernomas: A Common Mechanism.

CADASIL and Cavernomas: A Common Mechanism.

Primary involvement of neurovascular coupling in cerebral autosomal-dominant arteriopathy with subcortical infarcts and leukoencephalopathy.

Cerebral autosomal-dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is the most frequent monogenic cause of cerebral ischemia, but reliable biomarkers to monitor the disease are lacking. To evaluate cerebral autoregulation (CA), vasoreactivity (VR), and neurovascular coupling (NVC) in CADASIL patients through a battery of dynamic transcranial Doppler tests. We screened our database for all pre-dementia CADASIL cases. We monitored cerebral blood flow velocity (CBFV) with transcranial Doppler, blood pressure, and expiratory carbon dioxide (CO2) non-invasively. CA was assessed by transfer function from the spontaneous oscillations of blood pressure to CBFV, VR with inhalation of CO2 at 5%, and hyperventilation and NVC by the CBFV response to visual stimulation. We included 27 CADASIL patients and 20 healthy controls with similar age and sexes. CA and VR were similar between groups. However, NVC was significantly affected in CADASIL patients, with lower magnitudes of CBFV upsurge (overshoot 19 ± 5 vs 26 ± 6%, p = 0.013; gain 12 ± 7 vs 17 ± 5%, p = 0.003) and altered time behavior during visual stimulation (natural frequency 0.18 ± 0.06 vs 0.24 ± 0.06Hz, p = 0.005; rate time 0.7 ± 1.7 vs 2.7 ± 3.5s, p = 0.025). Our results express a primary and selective involvement of the neurovascular unit in CADASIL rather than a generalized cerebral vasomotor disturbance. Functional cerebrovascular testing could be useful in patient evaluation and monitoring.

R54C Mutation of NOTCH3 Gene in the First Rungus Family with CADASIL.

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.

The genetic spectrum and the evaluation of CADASIL screening scale in Chinese patients with NOTCH3 mutations

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is an inherited small artery disease caused by NOTCH3 gene mutation. Here we report clinical, pathological and genetic profiles of 29 newly-diagnosed CADASIL patients, evaluation of the CADASIL scale in Chinese CADASIL patients, and reanalysis of all reported mainland Chinese patients with identified NOTCH3 gene mutation. We found two novel mutations (p.C134G and p.C291Y) and 13 reported NOTCH3 mutations in the newly-diagnosed group. CADASIL scale score was less than the cutoff score in 19 of 53 Chinese patients with NOTCH3 mutation, generating only a sensitivity of 64.1%. At the time of study, the total number of genetically confirmed CADASIL cases reached 158 from 97 unrelated mainland Chinese families, with 9/97 (9.3%) sporadic patients. The NOTCH3 gene mutation profile showed 43 mutations, with hotspots in exon 4, followed by exon 3. The considerable variability in onset age and CADASIL scale score in patients carrying the same NOTCH3 missense mutation suggested no obvious phenotype–genotype correlation. In conclusion, we report two novel mutations which expand the NOTCH3 mutational spectrum. Exons 4 and 3 are hotspots in mainland Chinese patients with NOTCH3 mutation. The low sensitivity of CADASIL scale in our patients group indicated that the CADASIL scale should be refined according to the clinical characteristics of Chinese CADASIL patients when used in Chinese populations.

Abstract 26: Prevalence of CADASIL and Fabry Disease in a Large Cohort of MRI defined Younger onset Lacunar Stroke

Background: Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), caused by mutations in the NOTCH3 gene, is the most common monogenic disorder causing lacunar stroke and cerebral small vessel disease (SVD). Fabry disease (FD) due to mutations in the GLA gene has been suggested as an underdiagnosed cause of stroke, and one feature is SVD. Previous studies reported varying prevalence of CADASIL and FD in stroke, most likely due to varying subtypes studied; no studies have looked at a large cohort of younger onset SVD. We determined the prevalence of CADASIL and FD in a well-defined, MRI verified cohort of patients with lacunar infarct. Methods: Caucasian patients with lacunar infarction, aged <=70 years (mean age 56.7 (SD8.5), range 20-70), were recruited from 72 specialist stroke centres throughout the UK as part of the Young Lacunar Stroke DNA Resource. All MRI’s and clinical histories were reviewed centrally. CADASIL screening was performed using denaturing high performance liquid chromatography (DHPLC) and sequencing in cases with a suspected variant. Exons 3, 4 5, 6, 8, 11, 18, 19 and 22 were screened which has been shown to detect 90% of mutations in a UK population. FD screening was performed using high-resolution melt curve analysis with sequencing confirmation. Results: Of 1,049 subjects four had pathogenic NOTCH3 mutations (R169C, R207C, R587C and C1222G) all resulting in loss of gain of a cysteine in the NOTCH3 protein. All four patients had confluent leukoaraiosis (Fazekas grade ≥2), and three had multiple infarcts. CADASIL prevalence overall was 0.4 (95% CI 0.1%-0.9%) and among cases with confluent leukoaraiosis 1.2% (95% CI 0.4%-2.8%). One additional patient had a missense mutation in the GLA gene (R118C) of uncertain significance; conflicting data exists pathogenicity of this mutation. Conclusions: CADASIL cases can be detected in younger onset apparently sporadic lacunar stroke, but are rare. FD screening in this patient group has a minimal pick-up.

Genetically proven cerebral autosomal-dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) in a 3-year-old

Cerebral autosomal-dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) has always been considered to be a middle-age-onset disease. Diagnosis is confirmed by genetic testing and the finding of the Notch3 mutation or by skin biopsy. Imaging plays a pivotal and crucial role in confirming this diagnosis by identifying white matter changes early in the disease. This can be useful in screening symptomatic patients with a family history of the disease. CADASIL cases have been reported recently in children. We report our experience with CADASIL in a 3-year-old boy.

Skin and Sural Nerve Biopsies: Ultrastructural Findings in the First Genetically Confirmed Cases of CADASIL in Serbia

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is an inherited vascular disorder caused by Notch3 gene mutations. The main histopathological hallmark is granular osmiophilic material (GOM) deposited in the close vicinity of vascular smooth muscle cells (VSMCs). The authors report the first 7 ultrastructurally and genetically confirmed cases of CADASIL in Serbia. Samples of skin and sural nerve were investigated by transmission electron microscopy. GOM deposits were observed around degenerated VSMCs in all the skin biopsies examined. Sural nerve biopsies revealed severe alterations of nerve fibers, endoneurial blood vessels with GOM deposits, endoneurial fibroblasts, and perineurial myofibroblasts. Total genomic DNA was extracted from peripheral blood leukocytes, and exons 2–6 of the Notch3 gene were amplified by PCR and subsequently sequenced. Four different mutations in exons 2 (Cys65Tyr), 3 (Gly89Cys and Arg90Cys), and 6 (Ala319Cys), which determine the CADASIL disease, were detected among all described patients. A novel missense mutation Gly89Cys involving exon 3 was detected. Due to the difficulties in the determination of the Notch3 mutations, these data suggest that electron microscopic analysis for GOMs in dermal vessel wall provides a rapid and reliable screening method for this disease.

CADASILの診断，病態，治療の進歩―本邦におけるCADASIL診断基準の作成―

During the past 10 years, our understanding of the pathomechanism and pathophysiology of cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) has improved through clinical examination, imaging studies, pathological studies, cell experiments and the development of transgenic mice. Although epidemiological studies of CADASIL in Japan have been limited, more than 100 cases of this condition have been diagnosed in Japan. In our laboratory, we diagnosed 37 CADASIL cases genetically and identified three features common to Japanese cases. One is the wide distribution of onset age for clinical symptoms other than migraine, with the onset of symptoms being later than age 60 in 22% of cases. Second, the majority (65%) of Japanese CADASIL cases have stroke risk factors, such as hypertension, hyperlipidemia, or smoking. Third, in 22% cases there was no definite family history of stroke. However, the previous diagnostic criteria proposed by Dabous excluded several definite cases in our cohort. Therefore, to avoid missing undiagnosed cases of CADASIL, we have generated new diagnostic criteria for Japanese CADASIL based on the knowledge accumulated during the past 10 years, and compared sensitivity of two criteria. In our diagnosed Japanese CADASIL cases, the sensitivity of the new criteria was 19% and 78% for probable and possible cases, respectively, and only one case was (Fig. 3) missed when using the new criteria. In comparison, the sensitivity of Dabous's was 11% and 51% for probable and possible cases, respectively, and 24% cases were excluded due to hypertension, elderly onset or no family history, although these cases showed recurrent strokes, white matter lesions and NOTCH3 mutations. Using our new criteria, diagnosis of CADASIL can be made even in cases with elderly onset, stroke risk factors, and obscure family history.

A case of CADASIL without characteristic anterior temporal pole lesion diagnosed by skin biopsy

A 40 year-old man with migraine presented cerebral ischemic attacks several times in one year. He had no risk factors for cerebrovascular disease including hypertension, but had strong family history suggesting autosomal dominant inheritance. A brain MRI on T(2) weighted and FLAIR images revealed patchy and confluent hyper intensity areas in the subcortical white matters and bilateral external capsules, while no anterior temporal pole lesions characteristic of CADASIL (cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy) were detected. His skin biopsy demonstrated granular osmiophilic materials (GOM) on the basement membrane of the vascular smooth muscle cells in dermis as shown by an electron microscope. The following mutational analysis of the Notch3 gene disclosed a missense mutation of p.Arg133Cys in exon 3. Molecular diagnosis of CADASIL may be time consuming because Notch3 is a huge gene and mutations may occur at multiple sites. GOM on skin biopsy is diagnostic especially in cases where anterior temporal pole involvement on MRI is negative.

A cortical form of CADASIL with cerebral Aβ amyloidosis

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) was diagnosed by genetic testing in a 53-year-old patient, 10 years before death. Following two strokes with partial recovery, he developed rapidly progressive cognitive decline 3 years before death. Neuropathology confirmed CADASIL. Characteristic arteriolar changes were associated with subcortical infarcts, and status cribrosus in basal ganglia and the cortico-subcortical junctions. Leukoencephalopathy was very mild. Severe arteriolar changes in the cerebral cortex and leptomeninges were associated with numerous intracortical microinfarcts. There was abundant Abeta deposition throughout the cerebral cortex, mainly as Aβ42 diffuse plaques, frequently periarteriolar. There was no cerebral amyloid angiopathy apart from rare Aβ40 deposits around Notch3-positive deposits. Amyloid plaques were rare. Tau pathology was minimal. Alzheimer disease associated with CADASIL has been described, but the few reported cases had abundant amyloid plaques, amyloid angiopathy, fibrillar plaques and neurofibrillary tangles. Aβ accumulation could result from abnormal Aβ synthesis or impaired elimination due to the arteriolar changes of CADASIL. We did not find Aβ deposits in our other CADASIL cases with milder cortical arteriolar changes. Additional genetic predisposing factors were not identified. This case suggests that besides the classical, purely subcortical form of CADASIL, a "cortical" form with numerous lacunar infarcts and Aβ deposition in the cerebral cortex may occur and may be difficult to differentiate clinically from Alzheimer disease.

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy resulting in stroke in an 11‐year‐old male

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is caused by mutations in the Notch3 gene on chromosome 19. The condition manifests itself clinically typically in the third to fifth decade with migraine and recurrent episodes of stroke or transient ischaemic attacks. We report the case of an 11-year-old male with CADASIL resulting in stroke with right hemiparesis and dysphasia. Acute magnetic resonance imaging suggested infarction in the left hemisphere; magnetic resonance angiography revealed calibre variation of the intracerebral arteries. The patient suffered from common migraine with five to six attacks per month for 3 years 6 months before the stroke. Attacks occurred early in the morning with severe one-sided headache, photophobia, nausea, and vomiting. Antimigraine medications had no effect. The family history revealed more cases of CADASIL, with an autosomal dominant pattern. The diagnosis of CADASIL was confirmed by the finding of the known mutation of the Notch3 gene running in the family. With treatment in a neurorehabilitation centre the patient recovered most of his functions with only discrete fine-motor and cognitive sequelae. Our case report highlights the need for paediatricians to consider CADASIL in childhood stroke as well as in migraine patients.

Cholinergic Neuronal Deficits in CADASIL

Previous evidence from MRI and acetylcholinesterase histochemistry suggests cholinergic fibers are affected in cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL). As a measure of cholinergic function, we assessed choline acetyltransferase (ChAT) activities in the frontal and temporal neocortices and the immunocytochemical distribution of ChAT and p75 neurotrophin receptor (P75(NTR)) by in vitro imaging in the nucleus basalis of Meynert of CADASIL subjects. ChAT activities were significantly reduced by 60% to 70% in frontal and temporal cortices of CADASIL cases, as were ChAT and P75(NTR) immunoreactivities in the nucleus basalis. Our findings suggest cholinergic neuronal impairment in CADASIL and implicate cholinomimetic therapy for subcortical vascular dementias.

Skin biopsy findings and results of neuropsychological testing in the first confirmed cases of CADASIL in Norway

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is characterized by mutations in the notch3 gene. The mutation can be demonstrated by a gene test. The first group of Norwegian patients with CADASIL confirmed by gene testing was recently described. The present study includes six of the original nine patients with demonstrated notch3 mutation plus one patient with symptoms, who had been unwilling to go through gene testing. These seven patients underwent skin biopsy for electron microscopy. One patient was cognitively too impaired, but six went through neuropsychological testing. By electron microscopy characteristic granular osmiophilic material (GOM) was detected in all skin biopsies. The material is seen as granular deposits in the basal lamina of the smooth muscle layer, often making impressions upon adjacent smooth muscle cells. It seems important that blood vessels over a certain size (diameter >20 microm) are examined. A varying extent of cognitive decline was noted amongst all by neuropsychological testing. In cases with multiple infarctions reduction of perceptual speed, visuospatial skills and working memory could be demonstrated. Four patients showed executive dysfunction.

Cerebellar arteriovenous malformation and vertebral artery aneurysm in a CADASIL patient

The presence of large vessels malformations has not been reported in cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL). We describe a CADASIL patient in whom a brain cerebellar arteriovenous malformation was revealed by magnetic resonance (MR) imaging. An MR angiogram documented also an aneurysm along the right intracranial vertebral artery at the junction with the posterior-inferior cerebellar artery. The aneurysm was successfully treated by means of endovascular coil embolization. No neurological complication occurred in our patient during the angiographic procedure. In this case, in addition to an incidental coexistence of CADASIL and large vessels abnormalities, a causal role of the Notch pathway alteration could be hypothesized. Dysregulation of the Notch pathway is linked to several human diseases besides CADASIL. In one of these (the Alagille syndrome) intracranial aneurysms are reported. This hypothesis contrasts however with the absence of similar reports in other CADASIL cases and needs corroboration in large series.

Typical pathological changes of CADASIL in the optic nerve

Visual impairment due to retinal and optic nerve changes in cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is more common than previously thought. Deposits of granular osmiophilic material (GOM) have been shown in the wall of retinal arterioles, though retinal infarcts and vascular occlusions have never been reported. Ischaemic optic neuropathy, on the other hand, has been reported in one case of CADASIL but no pathology reports of the optic nerve have been published. Here we report optic nerve morphological findings in the autopsy material of a 41-year-old woman with genetically assessed CADASIL. Longitudinal and transverse sections of optic nerves were examined. Classical histological methods (haematoxylin-eosin and Nissl) were performed. Diffuse pallor of myelin and rarefaction of optic nerve fibres were observed. Classical GOM was evident in the tunica media of vessels in the meninges and white matter. Arteriole lumina were slightly narrowed. In conclusion, the typical pathological changes of CADASIL occur in the optic nerve and may contribute to impairment of visual function in CADASIL.

CADASIL: underdiagnosed in psychiatric patients?

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is exclusively related to symptoms of the central nervous system. Retrospectively in up to 15% the initial presentation is psychiatric disturbances. In these cases the diagnosis often is delayed or missed. Two cases of CADASIL diagnosed in a psychiatric hospital are presented. Both patients were admitted to the gerontopsychiatric department (one because of a suicidal attempt and a depressive episode, the other because of cognitive decline and progressive personal neglect). Brain magnetic resonance imaging (MRI) showed severe leukoencephalopathy in the absence of cardiovascular risk factors. In both cases, diagnosis of CADASIL was made by the identification of specific granular osmiophilic material in skin biopsies. Brain MRI should be performed in all cases of late onset of severe psychiatric symptoms. CADASIL should be considered as a possible differential diagnosis whenever a marked leukoencephalopathy is detectable. Diagnosis can be verified by taking a skin biopsy or by specific genetic testing.

The pathogenesis of CADASIL: an update

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) appears to be the most common form of hereditary stroke disorder. CADASIL is associated with arterial smooth muscle degeneration linked to mutations in the Notch3 gene, whose product is a transmembrane receptor that functions in cell–cell communication. The pathogenesis of CADASIL remains unclear. Current research efforts are directed towards the elucidation of various features of the disorder including investigations on CADASIL-like disorders, early cognitive changes, specificity of neuroimaging for diagnosis, discovery of de novo mutations, the development of Notch3 transgenic mouse models and molecular cellular studies in Notch3 signaling. The genetics of cerebrovascular disorders (CVD) was virtually unknown until recently. Genetic associations may have been evaded because of widely variable phenotypes, even within monogenic disorders such as CADASIL. Several investigators have attempted genotype–phenotype correlation in CADASIL cases but the relationship between genetic alterations and overt manifestation of phenotype remains elusive. However, the elucidation of the genetics and pathogenesis of CADASIL have been important in further understanding of the primary vascular mechanisms that lead to ischemic blood flow and its consequences on neuronal survival. This report summarizes some of the highlights of the satellite symposium on CADASIL at Vas-Cog 2003.

An Italian case of CADASIL with mutation CGC-TCG in codon 1006, exon 19 Notch3 gene

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is commonly overlooked or misdiagnosed owing to its recent identification. It is characterized clinically by recurrent cerebral infarcts, usually appearing between the ages of 30 and 50 years, subcortical dementia, and pseudobulbar palsy. It begins with migraine with aura in approximately one-third of patients. The pathological hallmark of angiopathy is the presence of characteristic granular osmiophilic material (GOM) within the basal lamina of smooth muscle cells. The defective gene in CADASIL is Notch3, which encodes a large transmembrane receptor, and 70% of missense mutations are in exons 3 and 4. Each gene defect leads to either a gain or loss of a cysteine residue in the extracellular N-terminal domain of the molecule. We report the case of a 53-year-old woman admitted to the hospital for transient ischemic attack and stroke-like episodes recurrent since age 43 years. The patient had pseudobulbar palsy, pyramidal signs, and cognitive impairment but not frank dementia. Cerebral MRI showed periventricular diffuse and confluent ischemic lesions. Ultrastructural study revealed an abnormal deposition of granular osmiophilic material (GOM) within the basal lamina in skin capillaries. Direct sequence analysis of the Notch3 gene was performed. Since no mutation was detected in exons 3 and 4, the remaining exons were sequenced and a missense mutation, CGC-TGC in codon 1006 of exon 19 was found. The mutation led to a gain of a cysteine residue. This is the first missense mutation in codon 1006 of exon 19 of the Notch3 gene to be described in Italy and the second reported in the literature.