# Chapter 10: Gene therapy

The exponential growth of knowledge in the field of biology, as well as the rapid pace of technological development, are opening up possibilities that until recently would have been considered part of the science fiction genre. This naturally also applies to the field of genetics and its application in medicine. Gene therapy is a promising technology for treating diseases caused by errors in DNA. In humans, there are about 4,600 gene mutations of which have an external manifestation. Interestingly, mutations in a gene can manifest themselves differently in different people. Currently, there are more than 7,100 phenotypes whose molecular basis is known. Some of them are classified among diseases, including various forms of cancer, cardiovascular and neurodegenerative diseases, musculoskeletal disorders, and many others.