Associations between TOMM40 Poly-T Repeat Variants and Dementia in Cases with Parkinsonism.
File(s)
Accepted version
Author(s)
Lindqvist, D
Prokopenko, I
Londos, E
Middleton, L
Hansson, O
Type
Journal Article
Abstract
BACKGROUND: Mitochondrial dysfunction has been implicated in the pathophysiology of Parkinson's disease (PD)-related pathologies. OBJECTIVE: To investigate the role of the Translocase of the Outer Mitochondrial Membrane 40 homolog (TOMM40) variants in PD without dementia (PDND), PD with dementia (PDD) and in Dementia with Lewy bodies (DLB). METHODS: 248 individuals, including 92 PDND, 55 PDD, and 101 DLB, were included. The rs10524523 locus in the TOMM40 gene (TOMM40 poly-T repeat) is characterized by a variable number of T residues that were classified into three groups based on length; short (S), long (L), and very long (VL). We tested log-additive genetic model of association with dementia and adjusted for age, sex, and APOEɛ4 carrier status. We analyzed cerebrospinal fluid (CSF) levels of Aβ42 and Tau, biomarkers related to Alzheimer's disease (AD). RESULTS: PDD/DBL status and abnormal CSF AD biomarkers (Aβ42 and Aβ42/Tau ratio) were both associated with the APOEɛ4 allele (p < 0.014) and the L allele of TOMM40 poly-T repeat (p < 0.008). The VL allele was less frequently observed in the PDD/DLB group (p = 0.013). In APOE-ɛ4 adjusted analyses, the relationships between the L and VL alleles and dementia status as well as CSF AD biomarkers were not significant. When adjusting for APOE-ɛ4, however, there were associations between S carrier status and PDD/DLB (p = 0.019) and abnormal CSF levels of Aβ42/Tau ratio (p = 0.037) although these were not significant after adjustment for multiple comparisons. CONCLUSION: Our results do not support the notion that TOMM40 poly-T repeat variants have independent effects on PDD and DLB pathology. This relationship seems to be driven by APOE-ɛ4.
Date Issued
2016-01-09
Date Acceptance
2015-11-24
Citation
Journal of Parkinsons Disease, 2016, 6 (1), pp.99-108
ISSN
1877-7171
Publisher
IOS Press
Start Page
99
End Page
108
Journal / Book Title
Journal of Parkinsons Disease
Volume
6
Issue
1
Copyright Statement
© 2015 – IOS Press and the authors. All rights reserved
Sponsor
UCB PHARMA SA
Identifier
PII: JPD150693
Grant Number
4400041565
Subjects
APOE
DLB
PDD
Parkinson’s disease
TOMM40
Publication Status
Published