Sickle cell trait is an inherited blood disorder that affects 1 million to 3 million Americans with 8 to 10 percent of them being Black. The disease is caused by a single mutation in one gene and mainly occurs in people of African descent which causes agonizing pain, strokes and early death. However, recent advances in gene therapy may eventually lead to a cure for sickle cell disease.
Currently, the only treatment is a risky and costly bone marrow transplant. In a half-dozen clinical trials planned or underway, researchers are testing genetic therapies for sickle cell disease and some patients in those studies no longer have signs of the disease.
One of those patients is 21-year-old Brandon Williams of Chicago, who had four strokes by age 18. His older sister died of the disease. After experimental gene therapy, he no longer has symptoms of sickle cell disease, The New York Times reported.
According to researchers at the Dana-Farber/Boston Children’s Cancer and Blood Disorders Center a fetus and newborn produce a different kind of
red blood cell than an older child. Even newborns with the sickle cell gene make healthy blood cells, thanks to fetal hemoglobin, which allows a fetus to get enough oxygen from its mother’s blood. But the body usually stops making it a few months after birth.
About 12 years ago, researchers at the center identified the gene that controls the manufacturing of fetal hemoglobin, called BCL11A. If they could just keep this gene from shutting off production of fetal hemoglobin, they reasoned, they could prevent most or all of the symptoms of sickle cell.
However, the caveat was figuring out how to make the genetic fix to every red blood cell, and not to other cells where it might cause side effects. Luckily through years of experimentation, the researchers learned how to infect the right cells with a virus that inserts the genetic fix. Once the cells are edited, they can be infused back into the body of a patient whose own red blood cells have been killed with chemotherapy.
Then, they should start making enough fetal hemoglobin to prevent problems from sickle cell.
Despite promising results, it’s unclear if the effects of treatment will last and it’s likely to be at least three years before a genetic therapy for sickle cell disease is approved.
“We are in uncharted territory,” Dr. David A. Williams, chief scientific officer at
Boston Children’s Hospital, told The Times.
“This would be the first genetic cure of a common genetic disease,” Dr. Edward Benz, professor of medicine at Harvard Medical School, told The Times.
For more information on sickle cell disease, visit our Health Conditions page on BlackDoctor.org.
By subscribing, you consent to receive emails from BlackDoctor.com. You may unsubscribe at any time. Privacy Policy & Terms of Service.
