rs3816587

This study applied Bayesian epistasis association mapping (BEAM/BEAM2) methods to genome-wide association studies data from the Welcome Trust Case Control Consortium (WTCCC) to identify high-order SNP interactions in rheumatoid arthritis. The analysis identified 319 high-order epistatic interactions across the genome, with many validated using data from the North American Rheumatoid Arthritis Consortium (NARAC). Key findings include inter-chromosomal interactions primarily on chromosomes 1, 3, 6, and 9, with enriched GO terms implicating synapse, calcium ion binding, and membrane pathways.

A case-control association study of 1,316 Korean RA patients and 1,006 controls found that rs7021206 in TRAF1 intron 3 is significantly associated with rheumatoid arthritis susceptibility (OR 1.21, P = 0.0037), while rs3761847, which is associated with RA in Caucasians, showed no association in Koreans due to different linkage disequilibrium patterns. Fine-mapping identified a 66-kb haplotype region spanning TRAF1 containing variants associated with RA across both Asian and Caucasian populations.