To investigate associations with autoimmune diseases, methods such as array comparative genomic hybridization (aCGH) and restriction enzyme digest variant ratio assays were developed, and large‐scale studies examining global CNVs suggested that FCGR2A and FCGR2B were also candidate genes for duplication or deletion events.191, 192, 193, 194. Here, FCGR2A is linked to autoimmune disease.