For instance, four genes, general transcription factor IIH subunit 4 (GTF2H4), human cytomegalovirus promoter 5 (HCP5), ATPase H+ transporting V1 subunit G2 (ATP6V1G2), and leukocyte specific transcript 1 (LST1), were detected in both RA and AS. Here, HCP5 is linked to rheumatoid arthritis.