This lecture covers gene therapy in the context of neurological diseases, focusing on monogenic and multifactorial disorders such as Canavan disease, Mucopolysaccharidosis, Spinal Muscular Atrophy, Alzheimer's disease, Parkinson disease, Amyotrophic lateral sclerosis, Huntington's disease, and Spinocerebellar ataxia type I. It explains the etiology of these diseases, methods of genetic material delivery to the brain, eyes, liver, and muscles, and the use of Cas9, sgRNA, and repair mechanisms for gene correction and insertion.