Molecular and Demographic study about Type 1 diabetes mellitus and associated with HLA typing Class II in sample of Iraqi children

Abstract

Background: Type1 diabetes mellitus is a serious disorder characterized destruction of pancreatic B-cell culminating in absolute insulin deficiency, the genetic factors contribute to the susceptibility of type 1 diabetes mellitus.

Objective: This study is carried out to increase knowledge demographic characters with type1 diabetes mellitus in children and its associated with Human Leukocyte Antigen (HLA) typing Class II

Subjects and methods: Fifty type1 diabetes mellitus patients compared to thirty apparently healthy individual were enrolled in this study with age ranged (3-13) years. Some demographic characters were analyzed and HLA were analyzed by polymerase chain reaction and sequence technique.

Result: This present study revealed that T1DM was found in 27 female and  23 male  with ratio 1.2:1with out significant difference.  It was noticed that the peak of occurrence of T1DM was at the age group 7-10 years, and onset age of T1DM 5-10 years with highly significant (p<0.001). There were  12(24%) of patients have positive family history, The second part of this study conducted on HLA typing Class II: DQA, DQB genes using two pairs of primers to amplify fragments with product size of 170bp and 270bp., for these genes  respectively. The sequencing of PCR product for samples of patients showed many genetic variants such as DQA*0503,  DQB*02,*03,  for Class II compared with control.

Conclusion: The present study demonstrate that no significant difference between age and gender groups of T1DM patients,  the highly incidence of T1DM occurrence was at the age group 7-10 years, it seems that association between the HLA Class II  revealed by sequencing was finding the variation in DQA*0503,DQB*02,DQB*03 alleles.