Gene polymorphisms of TNF--308 (G/A), IL-10-1082 (G/A), IL-6-174 (G/C) and IL-1Ra (VNTR) in Egyptian cases with type 1 diabetes mellitus

Background. Type 1 diabetes (T1D) is a genetically conditioned autoimmune disease in which cytokines play an important role. Objectives. To check for the association of polymorphisms of cytokine genes with type 1 diabetes. Subjects. This work included 50 cases with T1D and 98 healthy individuals from the Nile Delta region of Egypt. Cases included 20 males and 30 females with a median age of 25 and range of 15-50 years. Methods. DNA was amplified using PCR with sequence-specific primers for detection of polymorphisms related to tumor necrosis factor (TNF)--308 (G/A), interleukin (IL)-10-1082 (G/A), IL-6-174 (G/C), and IL-1Ra (VNTR). Results. Cases with T1D showed significant higher frequency of genotypes of TNF--308 AA (p0.001, odds ratio (OR)=7.91), IL-6-17CC (p0.05, OR=3.36) and IL-1Ra A1A1 (p0.05, OR=3.68) with significant lower frequencies of TNF--308 GA, and IL-1Ra A1A2 genotypes (p0.001 and 0.05, respectively). They also showed significant higher frequency of TNF--308 allele A (p0.05, OR=2.0), IL-1Ra allele A1 (p0.05, OR=2.98) with a significant lower frequency of TNF--308 G allele and IL-1Ra A2 allele (p0.05). No significant difference was detected among cases in relation to IL-10-1082 (G/A) genotypes or alleles nor in relation to age, sex, consanguinity or family history of the disease. Conclusions. Polymorphisms related to TNF- and IL-1Ra genes may be considered genetic markers for T1D among Egyptians with a potential impact on family counseling and management.