Editor: Akhmetova Aigerim
Translator: Bolysbek Dana
Author: Bolysbek Dana
Sickle cell anemia is an inherited blood disorder that occurs most commonly in people of African descent. The disease is caused by a mutation in the gene for the protein hemoglobin. The changes lead to the fact that red blood cells become rigid and take on a sickle shape. These cells can clog blood vessels, resulting in pain for the patient, and sometimes can lead to internal organ damage or stroke.
Two groups of researchers, working independently of each other, have found success in testing gene therapy for this disease.
The first team, with members from the United States, Germany, Canada and France, used the CRISPR-Cas9 gene editing system to increase fetal hemoglobin production in sickle cell anemia patients.
The second group consisted of members from Harvard Medical School and the Dana-Farber Cancer Institute. They used another method, which involved introducing RNA through a viral carrier that changed the expression of the fetal hemoglobin gene.
In both cases, doctors removed some of the patients' blood stem cells and attempted to disable the genetic switch that becomes inactivated in people with the disorder. The patient was then given chemotherapy to destroy their defective cells; then the altered stem cells were infused back into the patient. Next, scientists watched how these stem cells from the patient grew into normal blood cells.
Both teams were successful in their tests. The CRISPR-Cas9 group performed their first test 17 months ago, and since that time the patient has shown no signs of sickle- cell anemia pain. The team also tested a similar method to treat patients with beta-thalassemia, another inherited disorder in which patients produce little or no hemoglobin due to genetic mutations in approximately the same areas as patients with sickle cell anemia.
A second group of scientists have successfully carried out their method on six patients over the past few years.
Source: https://medicalxpress.com/news/2020-12-trials-results-gene-therapies-sickle-cell.html
