Transferability of European-derived Alzheimer's disease polygenic risk scores across multiancestry populations.

A polygenic score (PGS) for Alzheimer's disease (AD) was derived recently from data on genome-wide significant loci in European ancestry populations. We applied this PGS to populations in 17 European countries and observed a consistent association with the AD risk, age at onset and cerebrospinal fluid levels of AD biomarkers, independently of apolipoprotein E locus (APOE). This PGS was also associated with the AD risk in many other populations of diverse ancestries.

Association of rare missense variants with Alzheimer's disease in the Japanese population.

BackgroundLittle is known about the rare missense variants (RMVs) of in East Asians, including the Japanese, and their association with Alzheimer's disease (AD) and lipid metabolism.ObjectiveTo identify RMVs in the Japanese population and investigate their association with AD and lipid metabolism, including low-density lipoprotein cholesterol levels.Methods RMVs were explored in the Niigata (NIG; 2589 subjects) and Tohoku (ToMMo; 3307 subjects) cohorts.

Distinct patterns of cognitive traits in extreme old age and Alzheimer's disease.

Introduction: Clinical features of cognitive performance in extreme old age differ from those of pathological cognitive decline in Alzheimer's disease (AD).

Methods: We compared cognitive traits between 638 centenarians aged 100-115 years and 208 and 221 patients with AD from independent facilities.

Results: The presence of the apolipoprotein E (APOE) ε4 allele did not affect Mini-Mental State Examination (MMSE) scores in centenarians.

Inherited Prion Disease with a 5-octapeptide Repeat Insertion in the PRNP Gene Presenting with Familial Juvenile Dementia: A Case Report.

A 47-year-old man with a family history of juvenile dementia in his mother presented with memory loss and cognitive decline. Neuropsychological tests revealed impaired orientation, working memory, and apraxia. Magnetic resonance imaging revealed diffuse brain atrophy, and fluorodeoxyglucose positron emission tomography (PET) showed hypometabolism in the bilateral parietal lobes, posterior cingulate gyri, and precuneus, suggestive of Alzheimer's disease.

Transethnic analysis identifies SORL1 variants and haplotypes protective against Alzheimer's disease.

Introduction: The SORL1 locus exhibits protective effects against Alzheimer's disease (AD) across ancestries, yet systematic studies in diverse populations are sparse.

Methods: Logistic regression identified AD-associated SORL1 haplotypes in East Asian (N = 5249) and European (N = 8588) populations. Association analysis between SORL1 haplotypes and AD-associated traits or plasma biomarkers was conducted.

Long-standing preservation of levodopa response in progressive supranuclear palsy.

The clinical and neuropathological characteristics of progressive supranuclear palsy (PSP) with preservation of levodopa (L-dopa) response are described in this report. We present the case of a 73-year-old Japanese man with a 13-year history of dopa-responsive Parkinsonism and abnormalities observed in metaiodobenzylguanidine (MIBG) myocardial scintigraphy, suggesting Parkinson's disease. However, autopsy results revealed PSP pathology, including tuft-shaped astrocytes and globose-type neurofibrillary tangles, without Lewy body pathology.

Polygenic effects on the risk of Alzheimer's disease in the Japanese population.

Background: Polygenic effects have been proposed to account for some disease phenotypes; these effects are calculated as a polygenic risk score (PRS). This score is correlated with Alzheimer's disease (AD)-related phenotypes, such as biomarker abnormalities and brain atrophy, and is associated with conversion from mild cognitive impairment (MCI) to AD. However, the AD PRS has been examined mainly in Europeans, and owing to differences in genetic structure and lifestyle, it is unclear whether the same relationships between the PRS and AD-related phenotypes exist in non-European populations.

Missense mutation of NRAS is associated with malignant progression in neurocutaneous melanosis.

Neurocutaneous melanosis (NCM) is a rare congenital neurocutaneous syndrome characterized by congenital melanocytic nevus of skin and abnormal proliferation of leptomeningeal melanocytes. Early acquisition of post-zygotic somatic mutations has been postulated to underlie the pathogenesis of NCM. The pathogenesis of NCM remains to be fully elucidated, and treatment options have not been established.

Heterogenous Genetic, Clinical, and Imaging Features in Patients with Neuronal Intranuclear Inclusion Disease Carrying Repeat Expansion.

Neuronal intranuclear inclusion disease (NIID) is a neurodegenerative disorder that is caused by the abnormal expansion of non-coding trinucleotide GGC repeats in . NIID is clinically characterized by a broad spectrum of clinical presentations. To date, the relationship between expanded repeat lengths and clinical phenotype in patients with NIID remains unclear.

Novel partial deletions, frameshift and missense mutations of CSF1R in patents with CSF1R-related leukoencephalopathy.

Background And Purpose: Colony-stimulating factor 1 receptor (CSF1R)-related leukoencephalopathy is an adult-onset leukoencephalopathy caused by mutations in CSF1R. The present study aimed to explore the broader genetic spectrum of CSF1R-related leukoencephalopathy in association with clinical and imaging features.

Methods: Mutational analysis of CSF1R was performed for 100 consecutive patients with adult-onset leukoencephalopathy.

Biallelic Mutations and Deletion in a Family With Leigh Syndrome and Hereditary Neuropathy With Liability to Pressure Palsy.

Objectives: Leigh syndrome is a progressive encephalopathy characterized by symmetrical lesions in brain. This study aimed to investigate the clinicopathologic and genetic characteristics of a family with Leigh syndrome and hereditary neuropathy with liability to pressure palsy (HNPP).

Methods: Data from a Japanese family's clinical features, MRIs, muscle biopsy, and an autopsy were analyzed.

Different AT(N) profiles and clinical progression classified by two different N markers using total tau and neurofilament light chain in cerebrospinal fluid.

Background: The AT(N) classification was proposed for categorising individuals according to biomarkers. However, AT(N) profiles may vary depending on the markers chosen and the target population.

Methods: We stratified 177 individuals who participated in the Japanese Alzheimer's Disease Neuroimaging Initiative by AT(N) classification according to cerebrospinal fluid (CSF) biomarkers.

Four-repeat tauopathies and late-onset psychiatric disorders: Etiological relevance or incidental findings?

Argyrophilic grain disease (AGD), progressive supranuclear palsy (PSP) and corticobasal degeneration are four-repeat (4R) tauopathies that develop in the presenium or later. Whether these diseases are associated with the occurrence of late-onset psychiatric disorders remains unclear. To facilitate the accumulation of clinicopathological findings regarding this issue, we here present a selected series of 11 cases that clinically developed psychotic disorder (n = 7; age at onset: 41-75 years), depressive disorder (n = 1; 49 years), bipolar disorder (n = 2; 32 and 37 years) and somatoform disorder (n = 1; 88 years), and had at least one pathological hallmark of these tauopathies.

Genetics of Alzheimer's disease: an East Asian perspective.

Alzheimer's disease (AD) is an age-related multifactorial neurodegenerative disorder. Advances in genome technology, including next generation sequencing have uncovered complex genetic effects in AD by analyzing both common and rare functional variants. Multiple lines of evidence suggest that the pathogenesis of AD is influenced by multiple genetic components rather than single genetic factor.

Dissection of the polygenic architecture of neuronal Aβ production using a large sample of individual iPSC lines derived from Alzheimer's disease patients.

Genome-wide association studies have demonstrated that polygenic risks shape Alzheimer's disease (AD). To elucidate the polygenic architecture of AD phenotypes at a cellular level, we established induced pluripotent stem cells from 102 patients with AD, differentiated them into cortical neurons and conducted a genome-wide analysis of the neuronal production of amyloid β (Aβ). Using such a cellular dissection of polygenicity (CDiP) approach, we identified 24 significant genome-wide loci associated with alterations in Aβ production, including some loci not previously associated with AD, and confirmed the influence of some of the corresponding genes on Aβ levels by the use of small interfering RNA.

Brain TDP-43 pathology in corticobasal degeneration: Topographical correlation with neuronal loss.

Aims: Neuronal and glial inclusions comprising transactive response DNA-binding protein of 43 kDa (TDP-43) have been identified in the brains of patients with corticobasal degeneration (CBD), and a possible correlation between the presence of these inclusions and clinical phenotypes has been speculated. However, the significance of TDP-43 pathology in the pathomechanism of CBD has remained unclear. Here, we investigated the topographical relationship between TDP-43 inclusions and neuronal loss in CBD.

A functional variant of SHARPIN confers increased risk of late-onset Alzheimer's disease.

Late-onset Alzheimer's disease (LOAD) is the most common form of dementia, and its pathogenesis is multifactorial. We previously reported a rare functional variant of SHARPIN (rs572750141, NP_112236.3:p.

A Novel Heterozygous Missense Variant in the CIAO1 Gene in a Family with Alzheimer's Disease: The Val67Ile Variant Promotes the Interaction of CIAO1 and Amyloid-β Protein Precursor.

Familial dementia is a rare inherited disease involving progressive impairment of memory, thinking, and behavior. We report a novel heterozygous pathogenic variant (c.199G > A, p.