This study evaluated novel AI and deep learning generative methods to address AI bias for retinal diagnostic applications when specifically applied to diabetic retinopathy (DR). Bias often results from data imbalance. We specifically considered here a strong form of data imbalance corresponding to domain shift, where AI classifiers are faced at inference time with data and concepts they were not trained on initially (here the concept of diseased black individuals). A baseline DR diagnostics DLS designed to solve a two-class problem of referable vs not referable DR was used. We modified the public domain Kaggle-EyePACS dataset (88,692 fundi and 44,346 individuals), which was originally designed to be diverse with regard to ethnicity, as follows: 1) we expanded it to include clinician-annotated labels for race since those were not publicly available; 2) we excluded training exemplars for diseased black individuals in training, but not testing, to construct a new scenario of data imbalance with domain shift. For this domain shifted scenario, the accuracy (95% confidence intervals [CI]) of the baseline DR diagnostics DLS for whites was 73.0% (66.9%,79.2%) vs. blacks of 60.5% (53.5%,67.3%], demonstrating disparity of AI performance as measured by accuracy across races. By contrast, an AI approach leveraging generative models was used to train a new diagnostic DLS with additional synthetically generated data for the missing subpopulation (diseased blacks), which achieved accuracy for whites of 77.5% (71.7%,83.3%) and for blacks of 70.0% (63.7%,76.4%), demonstrating closer parity in accuracy across races. The new debiased DLS also showed improvement in sensitivity of over 21% for blacks, with the same level of specificity, when compared with the baseline DLS. These findings demonstrate the potential benefits of using novel generative methods for debiasing AI.