Gene therapy can be used in the treatment of many diseases - cancer, AIDS or cardiovascular disorders. Its limited clinical applications mainly due to the difficulties associated with the introduction of genes into tissues and obtaining them effective expression. To date, most gene therapy protocols using a viral system. More often considered the possibility of using a vector constructed from the adeno-associated virus (adeno-associated virus, AAV). AAV vectors to efficiently infect cells that are dividing and non-dividing, integrate into the host genome. A series of experiments indicate that AAV vectors may be useful in the transfer of therapeutic genes into muscle cells, liver, neurons, or cancerous tumors.