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Objective The aim of the study was to characterize the clinical features of nine patients in three families with chorea-acanthocytosis (ChAc) sharing the same rare c.2343del mutation in the VPS13A gene. Methods Genetic test results, clinical description, magnetic resonance imaging ( MRI), and electroencephalography ( EEG), as well as laboratory results are summarized. Results ChAc is a rare genetic disorder characterized by hyperkinetic movements, seizures, cognitive decline, neuropsychiatric symptoms, and acanthocytes on peripheral blood smear. This unique cohort of nine patients is characterized by seizures as a first and prominent symptom. In our patients, other features of ChAc appeared later, including tics, other movement disorders, dysarthria, and mild to moderate cognitive decline. Significance Patients with chorea-acanthocytosis carrying the described rare mutation can present with focal, treatment-resistant seizures. [ABSTRACT FROM AUTHOR]

Background: Mutations in the presenilin-1 gene (PSEN1) have been identified in autosomal dominant early-onset cases of Alzheimer's disease (AD). Aims: To investigate different clinical phenotypes of siblings possessing the same heterozygous P264L mutation in the PSEN1 gene. Methods: We evaluated clinical features, neuroimaging results, and neuropsychological examinations. The PSEN1 gene and other dementia-related gene mutations were screened. Results: We clinically diagnosed the proband as atypical AD with frontotemporal dementia features and diagnosed the elder brother of the proband as typical AD, based on neuropsychological symptoms and a brain imaging examination including amyloid imaging data. A heterozygous P264L mutation in the PSEN1 gene was identified in both siblings. Conclusion: This study is one of few reports of AD siblings possessing the same mutation but exhibiting different clinical phenotypes in a Japanese family possessing a P264L mutation in the PSEN1 gene. The current results suggest that unknown modifiers, including both genetic and epigenetic factors, may alter the pathological and clinical phenotypes of a genetically predetermined disease. Copyright © 2012 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background/Aims: Semantic dementia (SD) is a clinical subclassification of frontotemporal lobar degeneration. Patients with 'pure SD' present with semantic memory impairment preceding the frontal symptoms, and there have been no reports of familial cases. Methods: We evaluated the clinical features of, and performed neuropsychological examinations on, the proband and two affected family members. Then we performed neuroimaging and genetic analysis of MAPT and other dementia-related genes in the proband. Results: All three cases had semantic memory impairment with loss of word meanings as the primary early symptom. We diagnosed all cases as pure SD and identified a P301L mutation in the MAPT gene of the proband. Conclusion: Although the P301L mutation identified here has been previously described as pathogenic for frontotemporal dementia with parkinsonism-17 (FTDP-17), the proband and his two affected relatives showed different clinical symptoms from those of typical FTDP-17 cases who carry the P301L mutation. Pathologically, pure SD usually shows a TAR DNA-binding protein proteinopathy, but the molecular understanding of SD is not well established. Although our cases were clinically pure SD, the proband has a tau gene mutation, which would lead to tauopathy. These findings suggest that reconsideration of the molecular understanding of SD is warranted. Copyright © 2011 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Schizophrenia is a common psychiatric disorder with a strong genetic contribution. Disease-associated chromosomal abnormalities in this condition may provide important clues, such as DISC1. In this study, 59 schizophrenia patients were analyzed by microarray comparative genomic hybridization (CGH) using custom bacterial artificial chromosome (BAC) microarray (4,219 BACs with 0.7-Mb resolution). Chromosomal abnormalities were found in six patients (10%): 46,XY,der(13)t(12;13)(p12.1; p11).ish del(5)(p11p12); 46,XY, ish del(17)(p12p12); 46,XX.ish dup(11)(p13p13); and 46,X,idic(Y)(q11.2); and in two cases, mos 45,X/46XX. Autosomal abnormalities in three cases are likely to be pathogenic, and sex chromosome abnormalities in three follow previous findings. It is noteworthy that 10% of patients with schizophrenia have (sub)microscopic chromosomal abnormalities, indicating that genome-wide copy number survey should be considered in genetic studies of schizophrenia. [ABSTRACT FROM AUTHOR]

Chorea-acanthocytosis is a neurodegenerative disorder with peripheral red cell acanthocytosis. Linkage of chorea-acanthocytosis to chromosome 9q21 has been found. We refined the locus region and identified a previously unknown, full-length cDNA encoding a presumably structural protein, which we called chorein. We found a deletion in the coding region of the cDNA leading to a frame shift resulting in the production of a truncated protein in both alleles of patients and in single alleles of obligate carriers. [ABSTRACT FROM AUTHOR]

Abstract: Chorea-acanthocytosis (ChAc) is a hereditary neurodegenerative disorder caused by loss of function mutations in the VPS13A gene encoding chorein. Recently, using a gene-targeting technique to delete exons 60–61, we produced a ChAc-model mouse that corresponds to a human disease mutation. In this study, a comparative microarray analysis of gene expression in the striatum revealed an increased level of gephyrin gene expression in the ChAc-model mice compared with wild type mice. Since gephyrin is known as a GABAA receptor-anchoring protein, we compared the protein-level expression and localization of gephyrin and the GABAA receptor α1 (GABRA1) and γ2 (GABRG2) subunits. Gephyrin and GABRG2 immunoreactivities in the striatum and hippocampus of the ChAc-model mice were significantly higher than those in the wild types. Our results suggest that chorein functional loss may lead to a compensatory upregulation of gephyrin and GABRG2 in the pathologic condition in ChAc. [Copyright &y& Elsevier]