Association of peripheral blood DNA methylation level with Alzheimer's disease progression.

Abstract

BACKGROUND:

Identifying biomarkers associated with Alzheimer's disease (AD) progression may enable patient enrichment and improve clinical trial designs. Epigenome-wide association studies have revealed correlations between DNA methylation at cytosine-phosphate-guanine (CpG) sites and AD pathology and diagnosis. Here, we report relationships between peripheral blood DNA methylation profiles measured using Infinium® MethylationEPIC BeadChip and AD progression in participants from the Alzheimer's Disease Neuroimaging Initiative (ADNI) cohort.

RESULTS:

The rate of cognitive decline from initial DNA sampling visit to subsequent visits was estimated by the slopes of the modified Preclinical Alzheimer Cognitive Composite (mPACC; mPACCdigit and mPACCtrailsB) and Clinical Dementia Rating Scale Sum of Boxes (CDR-SB) plots using robust linear regression in cognitively normal (CN) participants and patients with mild cognitive impairment (MCI), respectively. In addition, diagnosis conversion status was assessed using a dichotomized endpoint. Two CpG sites were significantly associated with the slope of mPACC in CN participants (P < 5.79 × 10-8 [Bonferroni correction threshold]); cg00386386 was associated with the slope of mPACCdigit, and cg09422696 annotated to RP11-661A12.5 was associated with the slope of CDR-SB. No significant CpG sites associated with diagnosis conversion status were identified. Genes involved in cognition and learning were enriched. A total of 19, 13, and 5 differentially methylated regions (DMRs) associated with the slopes of mPACCtrailsB, mPACCdigit, and CDR-SB, respectively, were identified by both comb-p and DMRcate algorithms; these included DMRs annotated to HOXA4. Furthermore, 5 and 19 DMRs were associated with conversion status in CN and MCI participants, respectively. The most significant DMR was annotated to the AD-associated gene PM20D1 (chr1: 205,818,956 to 205,820,014 [13 probes], Sidak-corrected P = 7.74 × 10-24), which was associated with both the slope of CDR-SB and the MCI conversion status.

CONCLUSION:

Candidate CpG sites and regions in peripheral blood were identified as associated with the rate of cognitive decline in participants in the ADNI cohort. While we did not identify a single CpG site with sufficient clinical utility to be used by itself due to the observed effect size, a biosignature composed of DNA methylation changes may have utility as a prognostic biomarker for AD progression.

• Authors: Qingqin S Li, Aparna Vasanthakumar, Justin W Davis, Kenneth B Idler, Kwangsik Nho, Jeffrey F Waring, Andrew J Saykin, Alzheimer’s Disease Neuroimaging Initiative (ADNI)
• Journal: Clinical epigenetics (Clin Epigenetics) Vol. 13 Issue 1 Pg. 191 (10 15 2021) ISSN: 1868-7083 [Electronic] Germany
• PMID: 34654479 (Publication Type: Journal Article, Research Support, N.I.H., Extramural, Research Support, Non-U.S. Gov't)
• Copyright: © 2021. The Author(s).

Chemical References

• Biomarkers

Topics

• Aged
• Aged, 80 and over
• Alzheimer Disease (blood, diagnosis, genetics)
• Biomarkers (analysis, blood)
• Cognitive Dysfunction (genetics)
• Cohort Studies
• DNA Methylation (genetics, physiology)
• Disease Progression
• Female
• Humans
• Male