Mitochondrial DNA Sequence Variation Associated with Dementia and Cognitive Function in the Elderly

作者:Tranah Gregory J*; Nalls Michael A; Katzman Shana M; Yokoyama Jennifer S; Lam Ernest T; Zhao Yiqiang; Mooney Sean; Thomas Fridtjof; Newman Anne B; Liu Yongmei; Cummings Steven R; Harris Tamara B; Yaffe Kristine
来源:Journal of Alzheimer's Disease, 2012, 32(2): 357-372.
DOI:10.3233/JAD-2012-120466

摘要

Mitochondrial dysfunction is a prominent hallmark of Alzheimer's disease (AD). Mitochondrial DNA (mtDNA) damage may be a major cause of abnormal reactive oxidative species production in AD or increased neuronal susceptibility to oxidative injury during aging. The purpose of this study was to assess the influence of mtDNA sequence variation on clinically significant cognitive impairment and dementia risk in the population-based Health, Aging, and Body Composition (Health ABC) Study. We first investigated the role of common mtDNA haplogroups and individual variants on dementia risk and 8-year change on the Modified Mini-Mental State Examination (3MS) and Digit Symbol Substitution Test (DSST) among 1,631 participants of European genetic ancestry. Participants were free of dementia at baseline and incidence was determined in 273 cases from hospital and medication records over 10-12 follow-up years. Participants from haplogroup T had a statistically significant increased risk of developing dementia (OR = 1.86, 95% CI = 1.23, 2.82, p = 0.0008) and haplogroup J participants experienced a statistically significant 8-year decline in 3MS (beta = -0.14, 95% CI = -0.27, -0.03, p = 0.0006), both compared with common haplogroup H. The m. 15244A>G, p.G166G, CytB variant was associated with a significant decline in DSST score (beta = -0.58, 95% CI -0.89, -0.28, p = 0.00019) and the m.14178T>C, p.I166V, ND6 variant was associated with a significant decline in 3MS score (beta = -0.87, 95% CI-1.31, -3.86, p = 0.00012). Finally, we sequenced the complete similar to 16.5 kb mtDNA from 135 Health ABC participants and identified several highly conserved and potentially functional nonsynonymous variants unique to 22 dementia cases and aggregate sequence variation across the hypervariable 2-3 regions that influences 3MS and DSST scores.

  • 出版日期2012