Treatment of sickle cell anemia by CRISPR

Gene editing is a novel technology used by creating any sequence of DNA with programmable nucleases. Genome editing includes: 1- meganuclease 2- zinc finger nuclease 3- Transcription activator-like effector nuclease and 4- clustered regularly interspaced short palindromic repeats (CRISPR). Genome editing is the most favorable therapeutic choice in treating genetic disorders such as sickle cell disorder by using CRISPR. Sickle cell disease is an inherited disease caused by point mutation of beta-globin protein genome. This mutation caused RBCs malfunction and patients suffered from awful pain and many other complications without definitive cure until now. CRISPR is the bacterial complex discovered in 1987 when scientists studied on bacteria and found it as a defensive method against viruses. It formed in two parts, a nuclease called CAS-9 and a guide portion of RNA sequence. In 2013, scientists used CRISPR as a gene-editing tool in the human genome. The hypothesis was that at the first thestem cells ofthe patient would be given, then inappropriate mutation of DNA was identified and cut by CRISPR, and corrected by the cell's DNA repair system and eventually performed an autologous transplant for the patient. Now the patient can produce normal cells. In several studies, scientists worked on this hypothesis and in one group of them, Dever et al used this method and their results showed thattheir correction was 25% of mice's RBCs. This method is successful because of its ability to cure such disease, lower costs and lower adverse effects than the other methods.

CRISPR, Gene editing, Sickle cell disease