Abstract

A genetic polymorphism called C1858T of protein tyrosine phosphatase, non-receptor type 22 (PTPN22) gene has been associated with autoimmune diseases Aim: To describe the association between two autoimmune diseases, namely type 1 diabetes (T1D) and celiac disease (CD) and tyrosine phosphatase gene polymorphisms (variant C1858T of PTPN22). Subjects and Methods: C1858T single-nucleotide polymorphism within the PTPN22 gene was genotyped in 209 patients with T1D, 43 celiac patients and 100 healthy controls. Results: CC gene frequency was 0.906 and 0.790 in CD patients and controls respectively( p < 0.01). All analyzed groups had a low frequency of the TT genotype. Compared with the other study groups, patients with T1D had a low frequency of CC genotype (0.636). Also, in these patients, there was a non-significant association between CC genotype and islet cell IA-2 auto antibodies (p < 0.065). Among CD patients, CC genotype was significantly associated with anti-transglutaminase or anti endomysial antibodies (p < 0.03). Conclusions: These results confirm the association of the genetic variant C1858T of PTPN22 with CD. In contrast to published data, this association was not found in T1D patients.