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issn:0003-99.2
1.  Comprehensive Search for Alzheimer Disease Susceptibility Loci in the APOE Region 
Archives of neurology  2012;69(10):1270-1279.
Objective
To evaluate the association of risk and age at onset (AAO) of Alzheimer disease (AD) with single-nucleotide polymorphisms (SNPs) in the chromosome 19 region including apolipoprotein E (APOE) and a repeat-length polymorphism in TOMM40 (poly-T, rs10524523).
Design
Conditional logistic regression models and survival analysis.
Setting
Fifteen genome-wide association study data sets assembled by the Alzheimer's Disease Genetics Consortium.
Participants
Eleven thousand eight hundred forty AD cases and 10 931 cognitively normal elderly controls.
Main Outcome Measures
Association of AD risk and AAO with genotyped and imputed SNPs located in an 800-Mb region including APOE in the entire Alzheimer's Disease Genetics Consortium data set and with the TOMM40 poly-T marker genotyped in a subset of 1256 cases and 1605 controls.
Results
In models adjusting for APOE ε4, no SNPs in the entire region were significantly associated with AAO at P<.001. Rs10524523 was not significantly associated with AD or AAO in models adjusting for APOE genotype or within the subset of ε3/ε3 subjects.
Conclusions
APOE alleles ε2, ε3, and ε4 account for essentially all the inherited risk of AD associated with this region. Other variants including a poly-T track in TOMM40 are not independent risk or AAO loci.
doi:10.1001/archneurol.2012.2052
PMCID: PMC3579659  PMID: 22869155
2.  Genetic and Clinical Features of Progranulin-Associated Frontotemporal Lobar Degeneration 
Archives of neurology  2011;68(4):488-497.
Objective
To assess the relative frequency of unique mutations and their associated characteristics in 97 individuals with mutations in progranulin (GRN), an important cause of frontotemporal lobar degeneration (FTLD).
Participants and Design
A 46-site International Frontotemporal Lobar Degeneration Collaboration was formed to collect cases of FTLD with TAR DNA-binding protein of 43-kDa (TDP-43)–positive inclusions (FTLD-TDP). We identified 97 individuals with FTLD-TDP with pathogenic GRN mutations (GRN+ FTLD-TDP), assessed their genetic and clinical characteristics, and compared them with 453 patients with FTLD-TDP in which GRN mutations were excluded (GRN− FTLD-TDP). No patients were known to be related. Neuropathologic characteristics were confirmed as FTLD-TDP in 79 of the 97 GRN+ FTLDTDP cases and all of the GRN− FTLD-TDP cases.
Results
Age at onset of FTLD was younger in patients with GRN+ FTLD-TDP vs GRN− FTLD-TDP (median, 58.0 vs 61.0 years; P<.001), as was age at death (median, 65.5 vs 69.0 years; P<.001). Concomitant motor neuron disease was much less common in GRN+ FTLDTDP vs GRN− FTLD-TDP (5.4% vs 26.3%; P<.001). Fifty different GRN mutations were observed, including 2 novel mutations: c.139delG (p.D47TfsX7) and c.378C>A (p.C126X). The 2 most common GRN mutations were c.1477C>T (p.R493X, found in 18 patients, representing 18.6% of GRN cases) and c.26C>A (p.A9D, found in 6 patients, representing 6.2% of cases). Patients with the c.1477C>T mutation shared a haplotype on chromosome 17; clinically, they resembled patients with other GRN mutations. Patients with the c.26C>A mutation appeared to have a younger age at onset of FTLD and at death and more parkinsonian features than those with other GRN mutations.
Conclusion
GRN+ FTLD-TDP differs in key features from GRN− FTLD-TDP.
doi:10.1001/archneurol.2011.53
PMCID: PMC3160280  PMID: 21482928
3.  Meta-Analysis confirms CR1, CLU, and PICALM as Alzheimer’s disease risk loci and reveals interactions with APOE genotypes 
Archives of neurology  2010;67(12):1473-1484.
Objectives
To determine whether genotypes at CLU, PICALM, and CR1 confer risk for Alzheimer’s disease (AD) and whether risk for AD associated with these genes is influenced by APOE genotypes.
Design
Association study of AD and CLU, PICALM, CR1 and APOE genotypes.
Setting
Academic research institutions in the United States, Canada, and Israel.
Participants
7,070 AD cases, 3,055 with autopsies, and 8,169 elderly cognitively normal controls, 1,092 with autopsies from 12 different studies, including Caucasians, African Americans, Israeli-Arabs, and Caribbean Hispanics.
Results
Unadjusted, CLU [odds ratio (OR) = 0.91, 95% confidence interval (CI) = 0.85 – 0.96 for single nucleotide polymorphism (SNP) rs11136000], CR1 (OR = 1.14, CI = 1.07 – 1.22, SNP rs3818361), and PICALM (OR = 0.89, CI = 0.84 – 0.94, SNP rs3851179) were associated with AD in Caucasians. None were significantly associated with AD in the other ethnic groups. APOE ε4 was significantly associated with AD (ORs from 1.80 to 9.05) in all but one small Caucasian cohort and in the Arab cohort. Adjusting for age, sex, and the presence of at least one APOE ε4 allele greatly reduced evidence for association with PICALM but not CR1 or CLU. Models with the main SNP effect, APOE ε4 (+/−), and an interaction term showed significant interaction between APOE ε4 (+/−) and PICALM.
Conclusions
We confirm in a completely independent dataset that CR1, CLU, and PICALM are AD susceptibility loci in European ancestry populations. Genotypes at PICALM confer risk predominantly in APOE ε4-positive subject. Thus, APOE and PICALM synergistically interact.
doi:10.1001/archneurol.2010.201
PMCID: PMC3048805  PMID: 20697030
4.  The Spectrum of Mutations in Progranulin 
Archives of neurology  2010;67(2):161-170.
Background
Mutation in the progranulin gene (GRN) can cause frontotemporal dementia (FTD). However, it is unclear whether some rare FTD-related GRN variants are pathogenic and whether neurodegenerative disorders other than FTD can also be caused by GRN mutations.
Objectives
To delineate the range of clinical presentations associated with GRN mutations and to define pathogenic candidacy of rare GRN variants.
Design
Case-control study.
Setting
Clinical and neuropathology dementia research studies at 8 academic centers.
Participants
Four hundred thirty-four patients with FTD, including primary progressive aphasia, semantic dementia, FTD/amyotrophic lateral sclerosis (ALS), FTD/motor neuron disease, corticobasal syndrome/corticobasal degeneration, progressive supranuclear palsy, Pick disease, dementia lacking distinctive histopathology, and pathologically confirmed cases of frontotemporal lobar degeneration with ubiquitin-positive inclusions (FTLD-U); and 111 non-FTD cases (controls) in which TDP-43 deposits were a prominent neuropathological feature, including subjects with ALS, Guam ALS and/or parkinsonism dementia complex, Guam dementia, Alzheimer disease, multiple system atrophy, and argyrophilic grain disease.
Main Outcome Measures
Variants detected on sequencing of all 13 GRN exons and at least 80 base pairs of flanking introns, and their pathogenic candidacy determined by in silico and ex vivo splicing assays.
Results
We identified 58 genetic variants that included 26 previously unknown changes. Twenty-four variants appeared to be pathogenic, including 8 novel mutations. The frequency of GRN mutations was 6.9% (30 of 434) of all FTD-spectrum cases, 21.4% (9 of 42) of cases with a pathological diagnosis of FTLD-U, 16.0% (28 of 175) of FTD-spectrum cases with a family history of a similar neurodegenerative disease, and 56.2% (9 of 16) of cases of FTLD-U with a family history.
Conclusions
Pathogenic mutations were found only in FTD-spectrum cases and not in other related neurodegenerative diseases. Haploinsufficiency of GRN is the predominant mechanism leading to FTD.
doi:10.1001/archneurol.2009.328
PMCID: PMC2901991  PMID: 20142524
5.  Preclinical Evidence of Alzheimer Changes: Convergent Cerebrospinal Fluid Biomarker and Fluorodeoxyglucose Positron Emission Tomography Findings 
Archives of neurology  2009;66(5):632-637.
Background
Alterations in cerebrospinal fluid (CSF) tau and β–amyloid peptide 1–42 (Aβ42) levels and rates of cerebral glucose (CMRglu) on fluorodeoxyglucose positron emission tomography (FDG PET) occur years before clinical symptoms of Alzheimer’s disease (AD) become manifest, but their relationship remains unclear.
Objective
To determine whether CSF AD biomarker levels and CMRglu in healthy individuals correlate in brain structures affected early in AD.
Design
Cohort study.
Setting
Alzheimer’s disease research center.
Participants
Twenty individuals without dementia, aged 46 to 83 years.
Interventions
Lumbar CSF sampling and FDG-PET imaging of CMRglu. The CSF Aβ42, tau, and tau phosphorylated at threonine 181 (p–tau181) levels were measured using immunobead–based multiplex assays.
Main Outcome Measures
Correlations between CMRglu and CSF biomarker levels were analyzed via voxel–based and volume–of–interest approaches.
Results
Voxel–based analyses demonstrated significant negative correlations between CSF tau and p–tau181 levels and CMRglu in the posterior cingulate, precuneus, and parahippocampal regions. In contrast, a limited positive correlation was found between CSF Aβ42 levels and CMRglu in the inferior temporal cortex. Volume–of–interest analyses confirmed negative associations between CSF tau and p–tau181 levels and CMRglu in the parietal and medial parietal lobes and a positive association between CSF Aβ42 levels and CMRglu in the parahippocampal gyrus.
Conclusions
In healthy individuals, higher CSF tau and p–tau181 concentrations were associated with more severe hypometabolism in several brain regions affected very early in AD, whereas lower CSF Aβ42 concentrations were associated with hypometabolism only in the medial temporal lobe. This suggests that early tau and Aβ abnormalities may be associated with subtle synaptic changes in brain regions vulnerable to AD. A longitudinal assessment of CSF and FDG–PET biomarkers is needed to determine whether these changes predict cognitive impairment and incipient AD.
doi:10.1001/archneurol.2009.59
PMCID: PMC2718788  PMID: 19433663
6.  Glucocerebrosidase Gene Mutations 
Archives of neurology  2008;65(3):379-382.
Background
Mutations in the glucocerebrosidase (GBA) gene have been reported to modify risk for Parkinson disease (PD) and dementia with Lewy bodies (DLB). However, these findings have not been consistently replicated, and most studies have had substantial methodological shortcomings.
Objective
To better assess the role of GBA variants in altering risk for Lewy body disorders.
Design
Case-control study.
Setting
Four movement disorder clinics in the Seattle, Washington, area.
Participants
Seven hundred twenty-one patients with PD, 554 healthy control subjects, and 57 patients with DLB.
Main Outcome Measures
Disease status and presence or absence of the 2 most common GBA mutations (N370S and L444P).
Results
We observed a significantly higher heterozygote frequency for the 2 mutations in patients with PD (2.9%; P<.001) and those with DLB (3.5%; P=.045) compared with control subjects (0.4%).
Conclusion
Our findings suggest that GBA mutations exert a large effect on susceptibility for Lewy body disorders at the individual level but are associated with a modest (approximately 3%) population-attributable risk in individuals of European ancestry.
doi:10.1001/archneurol.2007.68
PMCID: PMC2826203  PMID: 18332251
8.  Clinical and neuropathological features of the Arctic APP mutation causing early onset Alzheimer's disease 
Archives of neurology  2008;65(4):499-505.
Background
A majority of mutations within the amyloid β (Aβ) region of the amyloid precursor protein (APP) gene cause inherited forms of intracerebral haemorrhage. Most of these mutations may also cause cognitive impairment, but the Arctic APP mutation is the only known intra-Aβ mutation to date causing the more typical clinical picture of Alzheimer's disease (AD).
Objective
To describe features of one Swedish and one American family with the previously reported Arctic APP mutation.
Subjects
Affected and non-affected carriers of the Arctic APP mutation from the Swedish and American families were investigated clinically. In addition, one brain from each family was investigated neuropathologically.
Results
The clinical picture, with age at disease onset in the sixth to seventh decade of life and dysfunction in multiple cognitive areas, is indicative of AD and similar to the phenotype for other AD APP mutations. Several affected mutation carriers displayed general brain atrophy and reduced blood flow of the parietal lobe, as demonstrated by magnetic resonance imaging and single photon emission computed tomography. One Swedish and one American case with the Arctic APP mutation have come to autopsy, neither of which showed any signs of haemorrhage but revealed severe congophilic angiopathy, region-specific neurofibrillary tangle pathology as well as abundant amyloid plaques. Intriguingly, a majority of plaques from both of these cases had a characteristic ring-like character.
Conclusions
Overall, our findings corroborate that the Arctic APP mutation causes a clinical and neuropathological picture compatible with AD.
doi:10.1001/archneur.65.4.499
PMCID: PMC2723757  PMID: 18413473
Familial Alzheimer's disease; APP gene mutations; Arctic mutation; cerebral amyloid angiopathy; dementia; genealogy
9.  Lewy Body Pathology in Familial Alzheimer Disease 
Archives of neurology  2006;63(3):370-376.
Background
The origin and significance of Lewy bodies and neurites (Lewy body pathology [LBP]) in Alzheimer disease (AD) are poorly understood.
Objective
To examine LBP in the brainstem, limbic cortex, and neocortex of a large number of familial AD cases with mutations in 2 presenilin (PSEN) genes.
Methods
Twenty-five familial AD cases with 9 known PSEN 1 mutations and 14 familial AD cases with a single PSEN 2 mutation (N141I) were examined for LBP using α-synuclein immunohistochemistry and sampling of multiple brainstem and cortical regions.
Results
The amygdala was the most vulnerable site for LBP. In fact, virtually all (24 [96%] of 25 cases) of the PSEN 1 mutation cases had LBP in the amygdala. The PSEN 1 mutation cases also had more frequent LBP in the amygdala and neocortex than those with the PSEN 2 mutation. However, within families with a single mutation of either PSEN 1 or PSEN 2, there was frequent variability of the LBP.
Conclusion
These findings suggest that there are genetic influences on the presence of LBP in familial AD as demonstrated by the differences between PSEN 1 and PSEN 2 mutation cases.
doi:10.1001/archneur.63.3.370
PMCID: PMC1892620  PMID: 16533963

Results 1-9 (9)