| 1. |
- Bras, Jose, et al.
(author)
-
Genetic analysis implicates APOE, SNCA and suggests lysosomal dysfunction in the etiology of dementia with Lewy bodies.
- 2014
-
In: Human molecular genetics. - : Oxford University Press (OUP). - 1460-2083 .- 0964-6906. ; 23:23, s. 6139-6146
-
Journal article (peer-reviewed)abstract
- Clinical and neuropathological similarities between dementia with Lewy bodies (DLB), Parkinson's and Alzheimer's diseases (PD and AD, respectively) suggest that these disorders may share etiology. To test this hypothesis, we have performed an association study of 54 genomic regions, previously implicated in PD or AD, in a large cohort of DLB cases and controls. The cohort comprised 788 DLB cases and 2624 controls. To minimize the issue of potential misdiagnosis, we have also performed the analysis including only neuropathologically proven DLB cases (667 cases). The results show that the APOE is a strong genetic risk factor for DLB, confirming previous findings, and that the SNCA and SCARB2 loci are also associated after a study-wise Bonferroni correction, although these have a different association profile than the associations reported for the same loci in PD. We have previously shown that the p.N370S variant in GBA is associated with DLB, which, together with the findings at the SCARB2 locus, suggests a role for lysosomal dysfunction in this disease. These results indicate that DLB has a unique genetic risk profile when compared with the two most common neurodegenerative diseases and that the lysosome may play an important role in the etiology of this disorder. We make all these data available.
|
|
| 2. |
- Guerreiro, Rita, et al.
(author)
-
Genetic Variants and Related Biomarkers in Sporadic Alzheimer's Disease.
- 2015
-
In: Current genetic medicine reports. - : Springer Science and Business Media LLC. - 2167-4876. ; 3, s. 19-25
-
Journal article (peer-reviewed)abstract
- From a neuropathological perspective, elderly patients who die with a clinical diagnosis of sporadic Alzheimer's disease (AD) are a heterogeneous group with several different pathologies contributing to the AD phenotype. This poses a challenge when searching for low effect size susceptibility genes for AD. Further, control groups may be contaminated by significant numbers of preclinical AD patients, which also reduces the power of genetic association studies. Here, we discuss how cerebrospinal fluid and imaging biomarkers can be used to increase the chance of finding novel susceptibility genes and as a means to study the functional consequences of risk alleles.
|
|
| 3. |
- Guerreiro, Rita, et al.
(author)
-
Genome-wide analysis of genetic correlation in dementia with Lewy bodies, Parkinson's and Alzheimer's diseases.
- 2016
-
In: Neurobiology of Aging. - : Elsevier BV. - 1558-1497 .- 0197-4580. ; 38, s. 7-214
-
Journal article (peer-reviewed)abstract
- The similarities between dementia with Lewy bodies (DLB) and both Parkinson's disease (PD) and Alzheimer's disease (AD) are many and range from clinical presentation, to neuropathological characteristics, to more recently identified, genetic determinants of risk. Because of these overlapping features, diagnosing DLB is challenging and has clinical implications since some therapeutic agents that are applicable in other diseases have adverse effects in DLB. Having shown that DLB shares some genetic risk with PD and AD, we have now quantified the amount of sharing through the application of genetic correlation estimates, and show that, from a purely genetic perspective, and excluding the strong association at the APOE locus, DLB is equally correlated to AD and PD.
|
|
| 4. |
- Kun-Rodrigues, Celia, et al.
(author)
-
A comprehensive screening of copy number variability in dementia with Lewy bodies.
- 2019
-
In: Neurobiology of aging. - : Elsevier BV. - 1558-1497 .- 0197-4580. ; 75
-
Journal article (peer-reviewed)abstract
- The role of genetic variability in dementia with Lewy bodies (DLB) is now indisputable; however, data regarding copy number variation (CNV) in this disease has been lacking. Here, we used whole-genome genotyping of 1454 DLB cases and 1525 controls to assess copy number variability. We used 2 algorithms to confidently detect CNVs, performed a case-control association analysis, screened for candidate CNVs previously associated with DLB-related diseases, and performed a candidate gene approach to fully explore the data. We identified 5 CNV regions with a significant genome-wide association to DLB; 2 of these were only present in cases and absent from publicly available databases: one of the regions overlapped LAPTM4B, a known lysosomal protein, whereas the other overlapped the NME1 locus and SPAG9. We also identified DLB cases presenting rare CNVs in genes previously associated with DLB or related neurodegenerative diseases, such as SNCA, APP, and MAPT. To our knowledge, this is the first study reporting genome-wide CNVs in a large DLB cohort. These results provide preliminary evidence for the contribution of CNVs in DLB risk.
|
|
| 5. |
- Kun-Rodrigues, Celia, et al.
(author)
-
Analysis of C9orf72 repeat expansions in a large international cohort of dementia with Lewy bodies
- 2017
-
In: Neurobiology of Aging. - : Elsevier BV. - 0197-4580 .- 1558-1497. ; 49
-
Journal article (peer-reviewed)abstract
- . C9orf72 repeat expansions are a common cause of amyotrophic lateral sclerosis and frontotemporal dementia. To date, no large-scale study of dementia with Lewy bodies (DLB) has been undertaken to assess the role of . C9orf72 repeat expansions in the disease. Here, we investigated the prevalence of . C9orf72 repeat expansions in a large cohort of DLB cases and identified no pathogenic repeat expansions in neuropathologically or clinically defined cases, showing that . C9orf72 repeat expansions are not causally associated with DLB.
|
|
| 6. |
- Ly, Han, et al.
(author)
-
The association of circulating amylin with β-amyloid in familial Alzheimer's disease.
- 2021
-
In: Alzheimer's & dementia. - : Wiley. - 2352-8737. ; 7:1
-
Journal article (peer-reviewed)abstract
- This study assessed the hypothesis that circulating human amylin (amyloid-forming) cross-seeds with amyloid beta (Aβ) in early Alzheimer's disease (AD).Evidence of amylin-AD pathology interaction was tested in brains of 31 familial AD mutation carriers and 20 cognitively unaffected individuals, in cerebrospinal fluid (CSF) (98 diseased and 117 control samples) and in genetic databases. For functional testing, we genetically manipulated amylin secretion in APP/PS1 and non-APP/PS1 rats.Amylin-Aβ cross-seeding was identified in AD brains. High CSF amylin levels were associated with decreased CSF Aβ42 concentrations. AD risk and amylin gene are not correlated. Suppressed amylin secretion protected APP/PS1 rats against AD-associated effects. In contrast, hypersecretion or intravenous injection of human amylin in APP/PS1 rats exacerbated AD-like pathology through disruption of CSF-brain Aβ exchange and amylin-Aβ cross-seeding.These findings strengthened the hypothesis of circulating amylin-AD interaction and suggest that modulation of blood amylin levels may alter Aβ-related pathology/symptoms.
|
|
| 7. |
- Najar, Jenna, et al.
(author)
-
Polygenic risk scores for Alzheimer's disease are related to dementia risk in APOE ɛ4 negatives.
- 2021
-
In: Alzheimer's & dementia (Amsterdam, Netherlands). - : Wiley. - 2352-8729. ; 13:1
-
Journal article (peer-reviewed)abstract
- Studies examining the effect of polygenic risk scores (PRS) for Alzheimer's disease (AD) and apolipoprotein E (APOE) genotype on incident dementia in very old individuals are lacking.A population-based sample of 2052 individuals ages 70 to 111, from Sweden, was followed in relation to dementia. AD-PRSs including 39, 57, 1333, and 13,942 single nucleotide polymorphisms (SNPs) were used.AD-PRSs (including 39 or 57 SNPs) were associated with dementia (57-SNPs AD-PRS: hazard ratio 1.09, confidence interval 1.01-1.19, P=.03), particularly in APOE ɛ4 non-carriers (57-SNPs AD-PRS: 1.15, 1.05-1.27, P=4 × 10-3, 39-SNPs AD-PRS: 1.22, 1.10-1.35, P=2 × 10-4). No association was found with the other AD-PRSs. Further, APOE ɛ4 was associated with increased risk of dementia (1.60, 1.35-1.92, P=1 × 10-7). In those aged ≥95 years, the results were similar for the AD-PRSs, while APOE ɛ4 only predicted dementia in the low-risk tertile of AD-PRSs.These results provide information to identify individuals at increased risk of dementia.
|
|
| 8. |
|
|
| 9. |
- Skoog, Ingmar, 1954, et al.
(author)
-
A non-APOE polygenic risk score for Alzheimer's disease is associated with CSF neurofilament light in a representative sample of cognitively unimpaired 70-year-olds.
- 2021
-
In: The journals of gerontology. Series A, Biological sciences and medical sciences. - : Oxford University Press (OUP). - 1758-535X. ; 76:6, s. 983-990
-
Journal article (peer-reviewed)abstract
- The effect of Alzheimer's disease (AD) polygenic risk scores (PRSs) on amyloid and tau pathophysiology and neurodegeneration in cognitively unimpaired older adults is not known in detail. This study aims to investigate non-APOE AD-PRS and APOE ε4 in relation to AD pathophysiology evaluated by cerebrospinal fluid (CSF) biomarkers in a population-based sample of 70-year-olds. A total of 303 dementia-free individuals from the Gothenburg H70 Birth Cohort Studies were included. Genotyping was performed using the NeuroChip, and AD-PRSs were calculated. CSF levels of amyloid-β (Aβ42), total tau (t-tau), phosphorylated tau (p-tau), neurogranin (Ng), and neurofilament light (NfL) were measured with ELISA. Associations were found between non-APOE PRS and both NfL (p=0.001) and Aβ42 (p=0.02), and between APOE ε4 and Aβ42 (p=1e-10), t-tau (p=5e-4), and p-tau (p=0.002). Similar results were observed when only including individuals with CDR=0, except for no evidence of an association between non-APOE PRS and Aβ42. There was an interaction between non-APOE PRS and Aβ42 pathology status in relation to NfL (p=0.005); association was only present in individuals without Aβ42 pathology (p=0.0003). In relation to Aβ42, there was a borderline interaction (p=0.06) between non-APOE PRS and APOE ε4; association was present in ε4 carriers only (p=0.03). Similar results were observed in individuals with CDR=0 (n=246). In conclusion, among cognitively healthy 70-year-olds from the general population genetic risk of AD beyond the APOE locus was associated with NfL in individuals without Aβ42 pathology, and with Aβ42 in APOE ε4 carriers, suggesting these associations are driven by different mechanisms.
|
|
| 10. |
- Sundal, Christina, et al.
(author)
-
An AARS variant as the likely cause of Swedish type hereditary diffuse leukoencephalopathy with spheroids
- 2019
-
In: Acta Neuropathologica Communications. - : Springer Science and Business Media LLC. - 2051-5960. ; 7
-
Journal article (peer-reviewed)abstract
- Swedish type Hereditary Diffuse Leukoencephalopathy with Spheroids (HDLS-S) is a severe adult-onset leukoencephalopathy with the histopathological hallmark of neuraxonal degeneration with spheroids, described in a large family with a dominant inheritance pattern. The initial stage of the disease is dominated by frontal lobe symptoms that develop into a rapidly advancing encephalopathy with pyramidal, deep sensory, extrapyramidal and optic tract symptoms. Median survival is less than 10 years. Recently, pathogenic mutations in CSF1R were reported in a clinically and histologically similar leukoencephalopathy segregating in several families. Still, the cause of HDLS-S remained elusive since its initial description in 1984, with no CSF1R mutations identified in the family. Here we update the original findings associated with HDLS-S after asystematic and recent assessment of several family members. We also report the results from exome sequencing analysesindicating the p.Cys152Phe variant in the alanyl tRNA synthetase (AARS) gene as the probable cause of this disease. The variant affects an amino acid located in the aminoacylation domain of the protein and does not cause differences in splicing or expression in the brain. Brain pathology in one case after 10 years of disease duration showed the end stage of the disease to be characterized by widespread liquefaction of the white matter leaving only some macrophages and glial cells behind the centrifugally progressing front. These results point to AARS as a candidate gene for rapidly progressing adult onset CSF1R-negative leukoencephalopathies.
|
|
