Genetic disorders are caused by mutations in genes. These genes consist of DNA and are inherited by the organism by its parents. Genes code for specific amino acids, and they are so complex that we still do not completely comprehend the function of every gene in the human body so we cannot remove them in order to fix a disease. Moreover, every cell in an organism's body has the same genome (except the gametes) so it is not possible to delete the faulty gene from the cells.
