Parkinsonism Relat Disord
June 2023
Introduction: Dystonia type 24 is due to the mutation of the ANO3 gene. It generally consists of craniocervical dystonia associated with tremor; however, other neurological manifestations may also occur. Scientific literature has been expanding on its phenotype over the past few years.
View Article and Find Full Text PDFDeleterious variants of DYNC2H1 gene are associated with a wide spectrum of skeletal ciliopathies (SC). We used targeted parallel sequencing to analyze 25 molecularly unsolved families with different SCs. Deleterious DYNC2H1 variants were found in six sporadic patients and two monozygotic (MZ) twins.
View Article and Find Full Text PDFAm J Hum Genet
November 2021
Upregulated signal flow through RAS and the mitogen-associated protein kinase (MAPK) cascade is the unifying mechanistic theme of the RASopathies, a family of disorders affecting development and growth. Pathogenic variants in more than 20 genes have been causally linked to RASopathies, the majority having a dominant role in promoting enhanced signaling. Here, we report that SPRED2 loss of function is causally linked to a recessive phenotype evocative of Noonan syndrome.
View Article and Find Full Text PDFThe expanded CAG repeat number in gene causes Huntington disease (HD), which is a severe, dominant neurodegenerative illness. The accurate determination of the expanded allele size is crucial to confirm the genetic status in symptomatic and presymptomatic at-risk subjects and avoid genetic polymorphism-related false-negative diagnoses. Precise CAG repeat number determination is critical to discriminate the cutoff between unexpanded and intermediate mutable alleles (IAs, 27-35 CAG) as well as between IAs and pathological, low-penetrance alleles (i.
View Article and Find Full Text PDFDentato-Rubral-pallidoluysian atrophy (DRPLA) is a rare autosomal, dominant, progressive neurodegenerative disease that causes involuntary movements, mental and emotional problems. DRPLA is caused by a mutation in the ATN1 gene that encodes for an abnormal polyglutamine stretch in the atrophin-1 protein. DRPLA is most common in the Japanese population, where it has an estimated incidence of 2 to 7 per million people.
View Article and Find Full Text PDFBackground: Paroxysmal movement disorders are rare and heterogeneous genetic conditions characterized by the recurrence of transient involuntary movements.
Phenomenology Shown: The phenomenology of a paroxysmal kinesigenic dyskinesia in a young professional athlete.
Educational Value: Providing basic clinical and genetic elements for the early recognition and diagnosis of a rare movement disorder.
Background: Huntington's disease is a rare, neurodegenerative disease caused by an expanded CAG repeat mutation in the huntingtin gene. Compared with adult-onset Huntington's disease, juvenile Huntington's disease (onset ≤20 years) is even rarer and has not been studied extensively. We aimed to further characterise juvenile Huntington's disease by examining the effect of CAG repeat size on disease presentation, progression, and survival.
View Article and Find Full Text PDFAtrioventricular septal defect (AVSD) may occur as part of a complex disorder (e.g., Down syndrome, heterotaxy), or as isolate cardiac defect.
View Article and Find Full Text PDFJuvenile Onset Huntington's Disease (JOHD) is a rare variant of HD withage of onset ≤20 years, accounting for 3-10% of all HD patients. The rarity occurrence of JOHD cases, who severely progress towards mental and physical disability with atypical clinical manifestations compared to classical HD, are responsible of general lack of knowledge about this variant. We obtained a fully reprogrammed iPS cell line from fibroblasts of a JOHD patient carrying 65 CAG repeats and age at onset at age 15.
View Article and Find Full Text PDFHuntington's disease (HD) is an incurable, autosomal dominant, hereditary neurodegenerative disorder that typically manifests itself in midlife. This pathology is linked to the deregulation of multiple, as yet unknown, cellular processes starting before HD onset. A human iPS cell line was generated from skin fibroblasts of a subject at the presymptomatic life stage, carrying a polyglutamine expansion in HTT gene codifying Huntingtin protein.
View Article and Find Full Text PDFHuntington Disease (HD) is an autosomal dominant disorder characterized by motor, cognitive and behavioral features caused by a CAG expansion in the HTT gene beyond 35 repeats. The juvenile form (JHD) may begin before the age of 20years and is associated with expanded alleles as long as 60 or more CAG repeats. In this study, induced pluripotent stem cells were generated from skin fibroblasts of a 8-year-old child carrying a large size mutation of 84 CAG repeats in the HTT gene.
View Article and Find Full Text PDFObjective: Gingival overgrowth is a side effect associated with some distinct classes of drugs, such as anticonvulsants, immunosuppressants, and calcium channel blockers. One of the main drugs associated with gingival overgrowth is the antiepileptic phenytoin, which affects gingival tissues by altering extracellular matrix metabolism. It has been shown that mutation of human SOS1 gene is responsible for a rare hereditary gingival fibromatosis type 1, a benign gingival overgrowth.
View Article and Find Full Text PDFMyoclonic status in nonprogressive encephalopathy (MSNE) is an early-onset, drug-resistant epileptic syndrome characterized by occurrence of continuous diffuse epileptiform abnormalities, associated with positive and/or negative phenomena and accompanied by transient and recurring motor, cognitive, and behavioral impairment. MSNE has been reported in Angelman syndrome (AS) secondary to 15q11-13 deletions or UBE3A mutations but not to paternal uniparental disomy (UPD). We describe the case of a male patient with AS caused by UPD who developed a myoclonic status (MS) associated with long-lasting fever of central origin, both promptly regressed with introduction of levetiracetam.
View Article and Find Full Text PDFNoonan syndrome (NS) is a relatively common developmental disorder with a pleomorphic phenotype. Mutations causing NS alter genes encoding proteins involved in the RAS-MAPK pathway. We and others identified Casitas B-lineage lymphoma proto-oncogene (CBL), which encodes an E3-ubiquitin ligase acting as a tumor suppressor in myeloid malignancies, as a disease gene underlying a condition clinically related to NS.
View Article and Find Full Text PDFAnalysis of 786 NF1 mutation-positive subjects with clinical diagnosis of neurofibromatosis type 1 (NF1) allowed to identify the heterozygous c.5425C>T missense variant (p.Arg1809Cys) in six (0.
View Article and Find Full Text PDFBackground: Multiplications of the SNCA gene that encodes alpha-synuclein are a rare cause of autosomal dominant Parkinson's disease (PD).
Methods: Here, we describe 2 novel families in which there is autosomal dominant PD associated with SNCA duplication, and we compare the clinical features of all known patients carrying 3 or 4 SNCA copies.
Results: Affected members in family A presented with early onset PD that was variably associated with nonmotor features, such as dysautonomia, cognitive deficits, and psychiatric disturbances.
Microdeletion 1q21.1 (del 1q21.1) and the reciprocal microduplication 1q21.
View Article and Find Full Text PDFEllis van Creveld syndrome and Weyers acrofacial dysostosis are allelic disorders caused by mutations in EVC or EVC2 genes. We illustrate the results of direct analysis of whole EVC and EVC2 genes' coding regions in 32 unrelated families with clinical diagnosis of Ellis van Creveld syndrome and in 2 families with Weyers acrofacial dysostosis. We identified mutations in 27/32 (84%) cases with Ellis van Creveld syndrome and 2/2 cases with Weyers acrofacial dysostosis.
View Article and Find Full Text PDFTriploidy occurs in about 1 to 3% of clinically recognizable pregnancies and is typically associated with growth restriction, craniofacial dysmorphisms and congenital anomalies. We report the case of a female fetus with prenatal diagnosis of complete triploidy, polysplenia, bilateral cleft-palate, horseshoe-kidneys and bilateral club-feet. Whereas bilateral cleft-palate, horseshoe-kidneys and bilateral club feet are known to be part of the triploidy-associated malformation spectrum, polysplenia, which usually occurs as part of the heterotaxia spectrum, has never been associated with triploidy.
View Article and Find Full Text PDFEur J Med Genet
September 2011
High prevalence of somatic mutations in the cardiac transcription factor genes NKX2.5 and GATA4 have been reported in the affected cardiovascular tissue of patients with isolated cardiac septal defects, suggesting a role of somatic mutations in the pathogenesis of these congenital heart defects (CHDs). However, all somatic mutations have been identified in DNA extracted from an archive of formalin-fixed cardiac tissues.
View Article and Find Full Text PDFRAS signaling plays a key role in controlling appropriate cell responses to extracellular stimuli and participates in early and late developmental processes. Although enhanced flow through this pathway has been established as a major contributor to oncogenesis, recent discoveries have revealed that aberrant RAS activation causes a group of clinically related developmental disorders characterized by facial dysmorphism, a wide spectrum of cardiac disease, reduced growth, variable cognitive deficits, ectodermal and musculoskeletal anomalies, and increased risk for certain malignancies. Here, we report that heterozygous germline mutations in CBL, a tumor-suppressor gene that is mutated in myeloid malignancies and encodes a multivalent adaptor protein with E3 ubiquitin ligase activity, can underlie a phenotype with clinical features fitting or partially overlapping Noonan syndrome (NS), the most common condition of this disease family.
View Article and Find Full Text PDFBackground: The pathogenesis of transposition of the great arteries (TGA) is still largely unknown. In general, TGA is not associated with the more common genetic disorders nor with extracardiac anomalies, whereas it can be found in individuals with lateralisation defects, heterotaxy and asplenia syndrome (right isomerism).
Objective: To analyse genes previously associated with heterotaxy in order to assess mutations in familial TGA unassociated with other features of laterality defects.
Criss-cross heart is a rare congenital cardiac defect characterized by crossing of the atrioventricular valves and of the inflow streams due to the twisting of the ventricles about their long axis. The aetiology of criss-cross heart has not been understood yet. Mice homozygous for Cx43 deficiency show a delay in normal looping of ascending limb of the heart tube, which temporarily retains a more symmetric middle position.
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