Spinocerebellar ataxia type 2 (SCA2) is an autosomal dominant, neurodegenerative disorder that affects the cerebellum and other areas of the central nervous system. We have devised a novel strategy, the direct identification of repeat expansion and cloning technique (DIRECT), which allows selective detection of expanded CAG repeats and cloning of the genes involved. By applying DIRECT, we identified an expanded CAG repeat of the gene for SCA2. CAG repeats of normal alleles range in size from 15 to 24 repeat units, while those of SCA2 chromosomes are expanded to 35 to 59 repeat units. The SCA2 cDNA is predicted to code for 1,313 amino acids-with the CAG repeats coding for a polyglutamine tract. DIRECT is a robust strategy for identification of pathologically expanded trinucleotide repeats and will dramatically accelerate the search for causative genes of neuropsychiatric diseases caused by trinucleotide repeat expansions.

Epilepsy is a common neurological disorder, and mutations in genes encoding ion channels or neurotransmitter receptors are frequent causes of monogenic forms of epilepsy. Here we show that abnormal expansions of TTTCA and TTTTA repeats in intron 4 of SAMD12 cause benign adult familial myoclonic epilepsy (BAFME). Single-molecule, real-time sequencing of BAC clones and nanopore sequencing of genomic DNA identified two repeat configurations in SAMD12. Intriguingly, in two families with a clinical diagnosis of BAFME in which no repeat expansions in SAMD12 were observed, we identified similar expansions of TTTCA and TTTTA repeats in introns of TNRC6A and RAPGEF2, indicating that expansions of the same repeat motifs are involved in the pathogenesis of BAFME regardless of the genes in which the expanded repeats are located. This discovery that expansions of noncoding repeats lead to neuronal dysfunction responsible for myoclonic tremor and epilepsy extends the understanding of diseases with such repeat expansion.

The aim of this study was to elucidate the characteristics, pathogenesis and treatment strategy of hypertrophic pachymeningitis that is associated with myeloperoxidase anti-neutrophil cytoplasmic antibody (ANCA). We retrospectively investigated clinical, radiological, immunological and pathological profiles of 36 patients with immune-mediated or idiopathic hypertrophic pachymeningitis, including 17 patients with myeloperoxidase-ANCA, four patients with proteinase 3-ANCA, six patients with other immune-mediated disorders, and nine patients with 'idiopathic' variety. Myeloperoxidase-ANCA-positive hypertrophic pachymeningitis was characterized by: (i) an elderly female predominance; (ii) 82% of patients diagnosed with granulomatosis with polyangiitis (previously known as Wegener's granulomatosis) according to Watts' algorithm; (iii) a high frequency of patients with lesions limited to the dura mater and upper airways, developing headaches, chronic sinusitis, otitis media or mastoiditis; (iv) a low frequency of patients with the 'classical or generalized form' of granulomatosis with polyangiitis involving the entire upper and lower airways and kidney, or progressing to generalized disease, in contrast to proteinase 3-ANCA-positive hypertrophic pachymeningitis; (v) less severe neurological damage according to the modified Rankin Scale and low disease activity according to the Birmingham Vasculitis Activity Score compared with proteinase 3-ANCA-positive hypertrophic pachymeningitis; (vi) increased levels of CXCL10, CXCL8 and interleukin 6 in cerebrospinal fluids, and increased numbers of T cells, neutrophils, eosinophils, plasma cells and monocytes/macrophages in autopsied or biopsied dura mater with pachymeningitis, suggesting TH1-predominant granulomatous lesions in hypertrophic pachymeningitis, as previously reported in pulmonary or renal lesions of granulomatosis with polyangiitis; and (vii) greater efficacy of combination therapy with prednisolone and cyclophosphamide compared with monotherapy with prednisolone. Proteinase 3-ANCA may be considered a marker for more severe neurological damage, higher disease activity and a higher frequency of the generalized form compared with myeloperoxidase-ANCA-positive hypertrophic pachymeningitis. However, categorization into 'granulomatosis with polyangiitis' according to Watts' algorithm and immunological or pathological features were common in both proteinase 3- and myeloperoxidase-ANCA-positive hypertrophic pachymeningitis. These data indicate that most patients with myeloperoxidase-ANCA-positive hypertrophic pachymeningitis should be categorized as having the central nervous system-limited form of ANCA-associated vasculitis, consistent with the concept of ophthalmic-, pulmonary- or renal-limited vasculitis.

The size of the (CAG)n repeat array in the 3' end of the MJD1 gene and the haplotype at a series of microsatellite markers surrounding the MJD1 gene were examined in a large cohort of Japanese and Caucasian subjects affected with Machado-Joseph disease (MJD). Our data provide five novel observations. First, MJD is associated with expansion fo the array from the normal range of 14-37 repeats to 68-84 repeats in most Japanese and Caucasian subjects, but no subjects were observed with expansions intermediate in size between those of the normal and MJD affected groups. Second, the expanded allele associated with MJD displays inter-generational instability, particularly in male meioses, and this instability was associated with the clinical phenomenon of anticipation. Third, the size of the expanded allele is not only inversely correlated with the age-of-onset of MJD (r = -0.738, p < 0.001), but is also correlated with the frequency of other clinical features [e.g. pseudoexophthalmos and pyramidal signs were more frequent in subjects with large repeats (p < 0.001 and p < 0.05 respectively)]. Fourth, the disease phenotype is significantly more severe and had an early age of onset (16 years) in a subject homozygous for the expanded allele, which contrasts with Huntington disease and suggests that the expanded allele in the MJD1 gene could exert its effect either by a dominant negative effect (putatively excluded in HD) or by a gain of function effect as proposed for HD. Finally, Japanese and Caucasian subjects affected with MJD share haplotypes at several markers surrounding the MJD1 gene, which are uncommon in the normal Japanese and Caucasian population, and which suggests the existence either of common founders in these populations or of chromosomes susceptible to pathologic expansion of the CAG repeat in the MJD1 gene.

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Background/Aims: We aimed to determine whether the concentration of serum C-reactive protein (CRP) is associated with cognitive function in an adult Japanese population. Methods: Participants of this cross-sectional study were from a subgroup of the Project in Sado for Total Health (PROST; n = 454; mean age, 70.5 years). The cognitive state was evaluated using the Mini-Mental State Examination (MMSE), and those with an MMSE score <24 were considered ‘cognitively declined'. Concentrations of serum high-sensitivity CRP were measured. Multiple logistic regression analysis was used to calculate odds ratios (ORs) for cognitive decline, adjusting for the covariates of age, sex, BMI, disease history, and APOE allele. Results: Of the 454 participants, 94 (20.7%) were cognitively declined. Relative to the lowest (first) quartile of CRP concentration, adjusted ORs were 1.29 (95% CI 0.61-2.75) for the second, 1.78 (95% CI 0.82-3.86) for the third, and 3.05 (95% CI 1.45-6.42) for the highest (fourth) quartiles (p for trend = 0.018). When data were stratified by sex, the association between CRP concentration and cognitive decline was observed only in women. Conclusion: Our findings suggest an association between higher CRP concentration and lower cognitive function. Chronic inflammation may affect cognitive function in adults, in particular women.

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Background/Aims: Evidence on modifiable factors associated with cognitive impairment in Japanese patients is scarce. This study aimed to determine modifiable factors for cognitive impairment in a Japanese hospital-based population. Methods: Subjects of this cross-sectional study were 1,143 patients of Sado General Hospital (Niigata, Japan) registered in the Project in Sado for Total Health (PROST) between June 2008 and September 2014. We assessed disease history, body mass index (BMI), leisure time physical activity, walking time, smoking and drinking habits, and consumption of vegetables, fruits, and green tea as predictors, with cognitive impairment defined by the Mini-Mental State Examination (score <24) as an outcome. Multiple logistic regression analysis was performed to calculate odds ratios (ORs) for cognitive impairment. Results: The mean subject age was 68.9 years, and the prevalence of cognitive impairment was 21.5%. Multivariate analysis revealed that age (p < 0.001), low BMI (<21.1; OR 1.39, 95% CI 1.12-1.72), a history of stroke (p = 0.003), a history of myocardial infarction (p = 0.038), low fruit consumption (p for trend = 0.012), and low green tea consumption (p for trend = 0.032) were independently associated with a higher prevalence of cognitive impairment. Conclusions: Modifiable factors, such as low BMI, low fruit consumption, and low green tea consumption, are associated with cognitive impairment. Longitudinal studies will be needed to confirm these findings.