Alternative Genetic Risk Variant for Alzheimer Disease Identified
Significant correlations were found between ABCA7 in the asymptomatic and early symptomatic disease stages.
HealthDay News — Certain Alzheimer disease (AD) risk variants are associated with brain amyloidosis, according to a study published online in JAMA Neurology.
Liana G. Apostolova, MD, from Indiana University in Indianapolis, and colleagues examined the correlation of the top 20 AD risk variants with brain amyloidosis using data from 322 cognitively normal control individuals, 496 individuals with mild cognitive impairment, and 159 individuals with AD dementia who had genome-wide association studies and 18F-florbetapir positron emission tomographic data from the Alzheimer Disease Neuroimaging Initiative (ADNI). The correlation of AD risk allele carrier status with florbetapir mean standard uptake value ratio was assessed using stepwise multivariable linear regression.
The researchers found that after apolipoprotein E ε4, the strongest correlation with amyloid deposition was seen for the adenosine triphosphate-binding cassette subfamily A member 7 (ABCA7) gene. There were significant correlations found between ABCA7 in the asymptomatic and early symptomatic disease stages. A stage-dependent association was seen for the fermitin family homolog 2 with brain amyloidosis, which was strongest in the mild cognitive impairment stage.
"This study found an association of several AD risk variants with brain amyloidosis," the authors write. "The data also suggest that AD genes might differentially regulate AD pathologic findings across the disease stages."
Two authors disclosed financial ties to the pharmaceutical industry. The study was partially funded by the ADNI, which received contributions from pharmaceutical companies.
Apostolova LG, Risacher SL, Duran T, et al. Associations of the top 20 Alzheimer disease risk variants with brain amyloidosis [published online January 16, 2018]. JAMA Neurol. doi:10.1001/jamaneurol.2017.4198