... responsible for the samples from the Biobank, designed the investigation, and participated in the data collection, statistical analysis and drafting of the manuscript.Competing interests The authors ... genotyping together with MJ,performed laboratory and statistical analysis, and contributed to preparation of the manuscript. GMA is the principal investigator, who, together withSRD, is responsible ... disease.AbbreviationsACPA: anti-citrullinated protein/peptide antibodies; CI: confidence interval;DIP: distal interphalangeal; OR: odds ratio; PsA: psoriatic arthritis; PTPN22:protein tyrosine phosphatase...