Anti-citrullinated peptide/protein antibody (ACPA)-negative RA shares a large proportion of susceptibility loci with ACPA-positive RA: a meta-analysis of genome-wide association study in a Japanese population

Table 1 Summary of study subjects

	Cases	Controls
GWAS meta-analysis
Number of subjects	670	16,891
Cohort	Kyoto, BBJP, IORRA	BBJP
Age*	60.4 ± 18.9	60.9 ± 12.5
Female ratio	81.6%	44.9%
Genotyping platform	Illumina HumanHap610-Quad BeadChip	Illumina HumanHap610-Quad BeadChip
	Illumina HumanHap300 BeadChip
	Illumina Human CNV370-Duo BeadChip
	Affymetrix Genome-wide Human SNP Array 6.0
RF positivity	46.3%	-
Replication study
Number of subjects	916	3,764
Cohort	Kyoto, BBJP, IORRA	Kyoto University
Age*	62.9 ± 13.7	59.3 ± 14.2
Female ratio	77.8%	48.4
Genotyping platform	Taqman Assay	Illumina HumanHap610-Quad BeadChip
Genotyping platform	Taqman Assay	Illumina HumanHap550 BeadChip
RF positivity**	40.0%	-

*Mean ± standard deviation. **Rheumatoid factor (RF) positivity rate of samples with RF data available. GWAS, genome-wide association studies; BBJP, Biobank Japan; IORRA, cohort of Tokyo Women’s Medical University; SNP, single nucleotide polymorphism.

ISSN: 1478-6362