PTPRC and rheumatoid arthritis: Cui et al., analyzing thirty-one risk allele variants, found that the major allele (G) of the rs10919563 PTPRC locus, which is a known predictor of RA risk, was associated with an increased response to anti-TNF therapy, with stronger association in seropositive patients (either anticitrullinated peptides antibodies, ACPA, and/or rheumatoid factors (RF)) [29].