الخلاصة

Background:Type 1 diabetes mellitus (T1DM) is an insulin-dependent form of diabetes, Cytotoxic T lymphocyte antigen-4 (CTLA-4)is a member of the immunoglobulin superfamily that is expressed by activated T cells and transmits an inhibitory signal to T cells.CTLA-4 coded byCTLA-4 gene on chromosome 2q33. Polymorphisms of CTLA-4 gene belong to the main genetic factors determining the susceptibility to T1DM. Methods: A case-control study was designed to include 120 Iraqi children with T1DM and 120 healthy children controls. The patients were diagnosed previously with T1DM by Al- Imam Al-Hassan center for endocrine and diabetes in Al-Imam Al-Hussein medical city in holy Kerbala province.Genotyping was performed using the Tetra-primer amplification refractory mutation system polymerase chain reaction technique (T-ARMS- PCR).The biochemical tests was HbA1ctest has been performed at central laboratory of Al-Imam Al-Hussein medical educational city. While the DNA extraction and PCR done at the research laboratory of the biochemistry department of the medical college of Kerbala university.Results: Risk factors of T1DM (Family history of diabetes mellitus, age at onset, gender) were found to be an independent risk factor for T1DM.The -318 C/T(rs5742909) polymorphism of CTLA-4 has anon-significantdifferences are revealedfor genotype and allele frequencies between T1DM patientsand the control group. By calculating the odds ratios, is less than (1), it issuggest that a person carrying T allele and C/T genotyping, decreased insusceptibility to be with T1DM. It is evident in the current study that the Tallele of the CTLA-4 -318 C/T was not associated with the occurrence ofT1DM and could not be considered as a risk factor for the development of thedisease.Conclusion: Our case-control study suggests that the CTLA-4(-318C/T) gene polymorphism is not associated with T1DM in the Kerbala children.