The 4th World Congress on Genetics, Geriatrics, and Neurodegenerative Diseases Research (GeNeDis 2020) focuses on the latest major challenges in scientific research, new drug targets, the development of novel biomarkers, new imaging techniques, novel protocols for early diagnosis of neurodegenerative diseases, and several other scientific advances, with the aim of better, safer, and healthier aging. The relation between genetics and its effect on several diseases are thoroughly examined in this volume. This volume focuses on the sessions from the conference on Genetics and Neurodegenerative Diseases.