Evaluation of the genetic association of the PTPN22 R620W polymorphism in familial and sporadic systemic lupus erythematosus.

Objective: The R620W (1858C-->T) polymorphism in PTPN22 has been implicated in type 1 diabetes mellitus, rheumatoid arthritis, Graves' disease, Hashimoto thyroiditis, autoimmune thyroid disease, and systemic lupus erythematosus (SLE). The aim of this study was to evaluate this polymorphism in patients with familial SLE and in those with sporadic SLE.

Methods: A total of 4,981 DNA samples were genotyped (from 1,680 SLE patients, 1,834 family members, and 1,467 controls).