Which of the following HLA types is associated with IDDM?
High-Yield Explanation
Major susceptibility gene for Type 1 DM is located in the HLA region on chromosome 6. 95% of patients with IDDM express HLA DR3 or DR4. Concordance rate of Type 1 DM in identical twins ranges between 40- 60%. Type 2 DM has a strong genetic component. The concordance of type 2 DM in identical twins is between 70 and 90%. Reference: Harrison's Principles of Internal Medicine, 18th Edition chapter 344.