Subsequent MR analyses identified 13 unique secondary genes (CTLA4, FCGR2A, FCRL3, SH2B3, MAPKAPK5-AS1, ALDH2, TMEM116, ADAM1B, RP11-367J7.2, IL6R, NCR3, FCGR3B, VCAM1) exhibiting significant associations with RA risk. Here, FCRL3 is linked to rheumatoid arthritis.