Siberian Journal of Life Sciences and AgricultureSiberian Journal of Life Sciences and AgricultureSiberian Journal of Life Sciences and Agriculture2658-66492658-6657Science and Innovation Center Publishing House48044310.12731/2658-6649-2026-18-3-1569ERIMWOФизиология человека и животныхHuman and Animal PhysiologyResearch ArticleThe role of-318C/T and +49A/G polymorphisms in the CTLA-4 gene in systemic lupus erythematosus Iraqi patientshttps://orcid.org/0000-0003-3492-912857190495864N-4596-2017JasiemThamer Mouhi
Iraq

PhD, Assistant Professor, Department of Microbiology

thamerm@kus.edu.iqCollege of Science, AL-Karkh University of Scienceen3006202630062026202618360720901202626032026Received:09012026Accepted:26032026Published:30062026Copyright ©; 2026, T.M. JasiemCopyright ©; 2026, Jasiem T.2026T.M. JasiemJasiem T.https://creativecommons.org/licenses/by-nc-nd/4.0https://journals.rcsi.science/2658-6649/article/view/480443480443/480443-1257459-1-SM.pdf

Background. In recent years, Systemic lupus Erythematosus (SLE) has become one of the common autoimmune diseases, where the body’s immune system unintentionally targets and damages its own tissues, there are many factors that responsible for pathogenicity one of the most importance is genetic factor, the essential protein which encoded from cytotoxic T lymphocyte associated protein 4 gene is the important protein for the negatively regulation of immune responses

Purpose. To determine the impact of variants -318C/T and +49A/G in the CTLA-4 gene in Systemic lupus Erythematosus Iraqi patients.

Materials and methods. 68 SLE Iraqi patients participated in the research study, 32 people in good healthy without any symptoms considers as a control group. The extract DNA was by used specific DNA Extraction Kit (gSYNCTM) made from Geneaid/Taiwan with technique “Polymerase chain reaction-restriction fragment length polymorphism” used for analysing the CTLA-4 genes -318C/T and the +49A/G polymorphisms.

Results. The - 318T and +49 G alleles frequency in the CTLA-4 gene carriers was significantly higher in patients compare with the control group (P = 0.008, OR 3.63, 95% CI 1.34 – 9.82; P = 0.007, OR 3.16, 95% CI 1.32 – 7.53, respectively), while the -318C and +49 A alleles frequency in the CTLA-4 gene carriers was low significantly when compare with the control group. Our results presented a significant relationship between CT heterozygous genotypes and T allele in the variant -318C/T in the CTLA-4 gene and AG heterozygous genotypes and G allele genotype in the +49G/A variant and SLE, addition that are more common in the SLE patients.

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