Nonmotor Symptoms in Patients with PARK2 Mutations

Decreased 123I-meta-iodobenzylguanidine (MIBG) uptake in MIBG myocardial scintigraphy, olfactory dysfunction, and rapid eye movement (REM) sleep behavior disorder (RBD) are considered useful early indicators of Parkinson disease. We investigated whether patients with PARK2 mutations exhibited myocardial sympathetic abnormalities using MIBG scintigraphy, olfactory dysfunction using the Sniffin' Sticks olfactory test, and RBD using polysomnography. None of the examined patients had RBD, and all except 1 patient exhibited an increase in the olfactory threshold. Moreover, one of the oldest patients exhibited impairment in identification and discrimination. Of 12 patients with PARK2 mutations, 4 patients, who were older than patients without abnormal uptake, exhibited decreased MIBG uptake. The results obtained in this study suggest that some patients with PARK2 mutations have increased thresholds of olfactory function and myocardial sympathetic dysfunction as nonmotor symptoms

FBXO7 mutations in Parkinson's disease and multiple system atrophy

Mutations in the F-box only protein 7 (FBXO7) gene, located on chromosome 22q12-q13, have recently been identified as having distinct clinical features in patients with hereditary Parkinson's disease (PD). Pathologically, a-synucleinepositive inclusions have been identified using anti-FBXO7 antibody staining techniques. In the present study, we screened entire exons of FBXO7 from 271 patients (231 PD and 40 multiple system atrophy [MSA]), of which 221 samples were of Japanese origin. The PD patients (n = 231) comprised 31 autosomal dominant, 82 autosomal recessive, and 118 sporadic forms. The 40 cases of MSA consisted of 8 autosomal dominant, 2 autosomal recessive, and 30 sporadic forms. We detected a Turkish patient with autosomal recessive inheritance, harboring a homozygous truncating mutation, Arg498Stop (p.R498X), in the FBXO7 gene. Consequently, we evaluated her and assessed the correlation between her clinical manifestations and genotypic analysis, although the FBXO7 p.R498X gene has lower frequency than others. Her age at onset was 17 years, and she clinically manifested with progressive parkinsonism and cognitive decline. In contrast, no pathogenic mutations in FBXO7 among PD and MSA patients of Japanese or other ethnicities were observed. Based on recent literature, we reviewed and compared the clinical findings and population differences between documented FBXO7 cases. (C) 2016 Elsevier Inc. All rights reserved

Isolated nigral degeneration without pathological protein aggregation in autopsied brains with LRRK2 p.R1441H homozygous and heterozygous mutations

Abstract Leucine-rich repeat kinase 2 (LRRK2) is the most common causative gene for autosomal dominant Parkinson’s disease (PD) and is also known to be a susceptibility gene for sporadic PD. Although clinical symptoms with LRRK2 mutations are similar to those in sporadic PD, their pathologies are heterogeneous and include nigral degeneration with abnormal inclusions containing alpha-synuclein, tau, TAR DNA-binding protein 43, and ubiquitin, or pure nigral degeneration with no protein aggregation pathologies. We discovered two families harboring heterozygous and homozygous c.4332 G > A; p.R1441H in LRRK2 with consanguinity, sharing a common founder. They lived in the city of Makurazaki, located in a rural area of the southern region, the Kagoshima prefecture, in Kyushu, Japan. All patients presented late-onset parkinsonism without apparent cognitive decline and demonstrated a good response to levodopa. We obtained three autopsied cases that all presented with isolated nigral degeneration with no alpha-synuclein or other protein inclusions. This is the first report of neuropathological findings in patients with LRRK2 p.R1441H mutations that includes both homozygous and heterozygous mutations. Our findings in this study suggest that isolated nigral degeneration is the primary pathology in patients with LRRK2 p.R1441H mutations, and that protein aggregation of alpha-synuclein or tau might be secondary changes

Screening PARK genes for mutations in early-onset Parkinson's disease patients from Queensland, Australia

A family history of Parkinson's disease (PD) is the most commonly reported risk factor after age, suggesting a genetic component to the disease in a sub-group of patients. Mutations in at least six genes have been identified that can lead to monogenic forms of PD. We screened a sample of 74 early-onset PD cases out of a cohort of 950 patients (onse

First report of a Japanese family with spinocerebellar ataxia type 10: The second report from Asia after a report from China

<div><p>Spinocerebellar ataxia type 10 (SCA10) is an autosomal-dominant cerebellar ataxia that is variably accompanied by epilepsy and other neurological disorders. It is caused by an expansion of the ATTCT pentanucleotide repeat in intron 9 of the <i>ATXN10</i> gene. Until now, SCA10 was almost exclusively found in the American continents, while no cases had been identified in Japan. Here, we report the first case of an SCA10 family from Japan. The clinical manifestations in our cases were cerebellar ataxia accompanied by epilepsy, hyperreflexia and cognitive impairment. Although the primary pathology in SCA10 in humans is reportedly the loss of Purkinje cells, brain MRI revealed frontal lobe atrophy with white matter lesions. This pathology might be associated with cognitive dysfunction, indicating that the pathological process is not limited to the cerebellum. Examination of the SNPs surrounding the SCA10 locus in the proband showed the “C-expansion-G-G-C” haplotype, which is consistent with previously reported SCA10-positive individuals. This result was consistent with the findings that the SCA10 mutation may have occurred before the migration of Amerindians from East Asia to North America and the subsequent spread of their descendants throughout North and South America.</p></div

Clinical Heterogeneity of Frontotemporal Dementia and Parkinsonism Linked to Chromosome 17 Caused by MAPT N279K Mutation in Relation to Tau Positron Emission Tomography Features

BACKGROUND: While mechanistic links between tau abnormalities and neurodegeneration have been proven in frontotemporal dementia and parkinsonism linked to chromosome 17 caused by MAPT mutations, variability of the tau pathogenesis and its relation to clinical progressions in the same MAPT mutation carriers are yet to be clarified.OBJECTIVES: The present study aimed to analyze clinical profiles, tau accumulations, and their correlations in 3 kindreds with frontotemporal dementia and parkinsonism linked to chromosome 17 attributed to the MAPT N279K mutation.METHODS: Four patients with N279K mutant frontotemporal dementia and parkinsonism linked to chromosome 17/MAPT underwent [11 C]PBB3-PET to estimate regional tau loads.RESULTS: Haplotype assays revealed that these kindreds originated from a single founder. Despite homogeneity of the disease-causing MAPT allele, clinical progression was more rapid in 2 kindreds than in the other. The kindred with slow progression showed mild tau depositions, mostly confined to the midbrain and medial temporal areas. In contrast, kindreds with rapid progression showed profoundly increased [11 C]PBB3 binding in widespread regions from an early disease stage.CONCLUSIONS: [11 C]PBB3-PET can capture four-repeat tau pathologies characteristic of N279K mutant frontotemporal dementia and parkinsonism linked to chromosome 17/MAPT. Our findings indicate that, in addition to the mutated MAPT allele, genetic and/or epigenetic modifiers of tau pathologies lead to heterogeneous clinicopathological features. © 2019 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society

Brain MRI of the proband (IV-1) and her mother (III-3).

<p>T1WI sagittal brain MRI image showings cerebellar atrophy in the proband (IV-1, 39 years old) and her mother (III-3, 65 years old) (A, B). Additionally, T1WI and FLAIR axial images show frontal atrophy with white matter lesions in the mother (III-3) (C, D).</p

Fluorescent repeat-primed PCR analysis in SCA10.

<p>Fluorescent repeat-primed PCR analysis of the <i>ATXN10</i> gene revealed an expanded ATTCT pentanucleotide repeat in the proband (IV-1) and in her mother (III-3).</p