FCN1 and systemic lupus erythematosus: Seven SNPs in FCN1 (rs2989727, rs1071583), FCN2 (rs7851696, rs17549193, rs7865453, rs17514136), and FCN3 (rs3813800) were genotyped in 200 SLE patients and 200 healthy controls using polymerase chain reaction (PCR) sequence-specific primer and PCR restriction fragment length polymorphism.