A single study for each showed no association between the PTPN22 788A allele and systemic sclerosis, giant cell arteritis, Henoch-schonlein purpura, uveitis, and Grave's disease.
This meta-analysis confirms that the PTPN22C1858T polymorphism is associated with SSc susceptibility and ACA status in Europeans, and that its prevalence is dependent on ethnicity.
Genetic studies in the systemic sclerosis (SSc), an autoimmune disease that clinically manifests with dermal and internal organ fibrosis and small vessel vasculopathy, have identified multiple susceptibility genes including HLA-class II, PTPN22, IRF5, and STAT4 which have also been associated with other autoimmune diseases, such as systemic lupus erythematosus (SLE).
PTPN22 haplotype analysis identified a strong association between SSc and the presence of a risk haplotype carrying the 1858T allele (P = 1.52 x 10(-7)) and a protective haplotype carrying the 1858C allele (P = 2.20 x 10(-16)) in our French Caucasian population.
The association of subsets of SSc with the PTPN22R620W polymorphism further strengthens the classification of SSc within the spectrum of autoimmune diseases and strongly suggests the involvement of common susceptibility genes and similarly disordered immunoregulatory pathways.