HLA-DRB1 and Alzheimer disease: In addition, when the patients were divided into two groups according to the age at the onset of AD (EOAD and LOAD), we observed that rs9271058 of HLA-DRB1 (dominant, overdominant, and additive models), rs9473117 of CD2AP (dominant and additive models), and rs73223431 of PTK2B (dominant, overdominant, and additive models) were possibly associated with EOAD.