Interaction between variants in CLU and MS4A4E modulates Alzheimer's disease risk.

Ebbert MT, Boehme KL, Wadsworth ME, Staley LA, Mukherjee S, Crane PK, Ridge PG, Kauwe JS.
Alzheimer's & dementia : the journal of the Alzheimer's Association. 2016 Feb;12(2):121-9.
Abstract
INTRODUCTION: Ebbert et al. reported gene-gene interactions between rs11136000-rs670139 (CLU-MS4A4E) and rs3865444-rs670139 (CD33-MS4A4E). We evaluate these interactions in the largest data set for an epistasis study. METHODS: We tested interactions using 3837 cases and 4145 controls from Alzheimer's Disease Genetics Consortium using meta-analyses and permutation analyses. We repeated meta-analyses stratified by apolipoprotein E (APOE) epsilon4 status, estimated combined odds ratio (OR) and population attributable fraction (cPAF), and explored causal variants. RESULTS: Results support the CLU-MS4A4E interaction and a dominant effect. An association between CLU-MS4A4E and APOE epsilon4 negative status exists. The estimated synergy factor, OR, and cPAF for rs11136000-rs670139 are 2.23, 2.45, and 8.0, respectively. We identified potential causal variants. DISCUSSION: We replicated the CLU-MS4A4E interaction in a large case-control series and observed APOE epsilon4 and possible dominant effect. The CLU-MS4A4E OR is higher than any Alzheimer's disease locus except APOE epsilon4, APP, and TREM2. We estimated an 8% decrease in Alzheimer's disease incidence without CLU-MS4A4E risk alleles and identified potential causal variants.
Consortium data used in this publication
ENCODE TF ChIP, DNase, RegulomeDB, table S3, S4, described in results
References