Genetic and diabetic auto-antibody markers in Saudi children with type 1 diabetes.

Human leukocyte antigen DRB1 and DQB1 contribute to the genetic susceptibility of type 1 diabetes (T1DM), and they are involved in the induction of the autoimmune destruction of pancreatic beta cells precipitating the disease. The objective of this study was to examine diabetic auto-antibodies (ICA-512, GAD65) and the HLA-DR/DQ genotype among T1DM Saudi children in a cross-sectional study conducted at King Khalid University and National Guard Hospitals, Riyadh. Subjects included in this study were 103 Saudi patients and 180 healthy controls. In all, 41% of patients were positive for ICA512 73.3% positive for GAD65, and 27.3% had both antibodies. The risk alleles were DRB1*0301 (odds ratio [OR] = 11.1); DRB1*0405 (OR = 6.02); DRB1*0401 (OR = 5.8); DQB1*0201 (OR, 17.69) and DQB1*0302 (OR = 3.77). In addition, the DRB1*03/04-DQB1*02/0302 (OR = 123.4) is positively associated with T1DM. However, DRB1*0403 (OR = 0.27), DRB1*1101 (OR = 0.049), DRB1*1307 (OR = 0.28), DRB1*1501 (OR = 0.12), DQB1*0301 (OR = 0.03), DQB1*0401 (OR = 0.04), and DQB1*0602 (OR = 0.16) were protective. Among GAD-positive patients, 81% were DRB1*0301, 68.75% were DQB1*0201, 62.5% were DRB1*0405, 43.75% were DQB1*0302, and 43.7% were DRB1*03/04. Among ICA512-positive patients, all were DRB1*0301, 66.6% were DQB1*0201, 55% were DRB1*0405, 33.3% were DQB1*0302, and 55% were DRB1*03/04. In conclusion, these results show a strong association of HLA-DQB1*0201/0302 and DRB1*03/04 with T1DM. Thus, combining genetic markers with autoantibody is useful in a screening program for early detection of T1DM among Saudi children.