PTPN22 and systemic lupus erythematosus: For example, the rate of recurrent miscarriage is higher in women with systemic lupus erythematosus than in healthy women; in point of fact anti-nuclear antibody and anti-cardiolipin antibody autoantibodies seemed to be important risk factors for the incidence of RPL (22, 23) and previous studies have indicated that there is a statistically significant correlation between the PTPN22 R620W mutation and the presence of these two autoantibodies (12, 24).