Table 1.

Genetic factors confirmed for or suggestive of association with anticitrulline-peptide antibody (ACPA)-positive and ACPA-negative rheumatoid arthritis

Factor	ACPA-positive rheumatoid arthritis	ACPA-negative rheumatoid arthritis
Confirmed	Human leucocyte antigen shared epitope alleles	Human leucocyte antigen DR3
	Protein tyrosine phosphatase nonreceptor 22 (PTPN22)
	Complement component 5-TNF receptor-associated factor 1 (C5-TRAF1)
	TNFα-induced protein 3-oligodendrocyte lineage transcription factor 3 (TNFAIP3-OLIG3)
Suggestive	Cytotoxic T lymphocyte antigen 4 (CTLA4)	Interferon regulatory factor 5 (IRF5)
	Signal transducer and activator of transcription 4 (STAT4)