Abraham Kalfoury
Background: It has been hypothesized that the major histocompatibility complex (MHC) genes are the primary genetic factor in the predisposition to type 1 diabetes mellitus (T1DM). It had also been reported that other loci outside the MHC contributed to T1DM susceptibility. In this study, we looked at a sample of Egyptian children to see how some variants of polymorphic sites in some genes that are linked to T1DM played a role.
Methods and subjects: This study included 60 healthy participants and 60 T1DM patients from Alexandria University Children's Hospital's diabetes clinic. The method of isopropanol precipitation was used to extract genomic DNA. Genotyping was performed on cytotoxic T-lymphocyte antigen-4 (CTLA-4) as well as the vitamin D receptor (VDR), interleukin 10 (IL-10), protein tyrosine phosphatase non-receptor 22 (PTPN22), and interleukin 18 (IL-18).
Results: The PTPN22 gene single nucleotide polymorphisms SNP-137 G>C (rs#187238), VDR Fok1 SNP T>A (rs#2228570), and SNP-1123 C>G (rs#2488457) showed a significant difference between patients and controls (P = 0.026, 0.030, and 0.003, respectively), according to the results of the logistic regression analysis. There was no significant difference between the genotype distributions of PTPN22 SNP-1858, CTLA-4 SNP 49, IL-10 SNP-819, IL-18 SNP-607, and VDR BsmI SNP G>A.
Conclusion: The presence of T1DM in Egyptian children may be influenced by the PTPN22 gene's SNP-1123 C>G (rs#2488457), VDR SNP-Fok1 T>A (rs#2228570), and IL-18 SNP-137 G>C (rs#187238). More populationbased, large-scale case-control studies are required.
KeywordsGenes; Genomic DNA; Single nucleotide polymorphism; Type 1 diabetes mellitus