Gene therapy includes modifying the genes within your body’s cells in order to treat or prevent disease. Your DNA is included in genes, which is the code that regulates much of your body’s appearance and function, from growing you taller to regulating your body systems. Disease can be caused by genes that do not function properly.
Gene therapy attempts to cure sickness or increase your body’s ability to fight disease by replacing a broken gene or adding a new gene. Gene therapy has the potential to treat a broad variety of ailments, including cancer, cystic fibrosis, heart disease, diabetes, hemophilia, and AIDS.
Gene therapy is an interesting technique that is currently being researched for the treatment of sickle cell disease. Currently, the medication is only provided as part of clinical trials. Researchers are currently optimistic that gene therapy treatment will be proved to be effective in curing the condition.
Today, it is obvious that our genes not only cause a wide range of disorders, but also harbor potential remedies. However, this was not always the case. It wasn’t until 1949 that scientists discovered a disease’s molecular cause – its origins in the genetic code. The disease was sickle cell disease, a genetic blood disorder that produces acute and chronic pain. Researchers are developing gene therapies to cure it nearly 75 years later.
People with sickle cell disease have a shorter life expectancy, living only into their late 40s on average, owing to strokes or organ damage caused by clogged blood arteries. Gene therapies attempt to modify life’s very information by replacing, inactivating, or repairing missing or faulty genes and thereby cure patients.
Erica Esrick
Sickle cell disease is caused by a mutation in a critical protein in hemoglobin, which aids in the transfer of oxygen in red blood cells. According to doctor Erica Esrick, hemoglobin generally permits “red blood cells to be highly floppy and malleable, and slip and slide through the blood arteries easily.” However, a single gene mutation, the HBB gene, causes hemoglobin to stack in long strings inside blood cells, giving them an inflexible, sickle form. Instead of being “squishy,” stiff red blood cells become lodged within blood vessels, obstructing blood flow.
Sickle cell disease affects millions of people worldwide, notably those with ancestors from Sub-Saharan Africa, the Middle East, and Southeast Asia. In the United States, for example, over 100,000 persons have the condition, the majority of them are Black or Latino. People with sickle cell disease have a shorter life expectancy, living only into their late 40s on average, owing to strokes or organ damage caused by clogged blood arteries. Esrick, of Boston Children’s Hospital and Harvard Medical School, and colleagues are using gene therapy to combat the disease.
Gene therapies attempt to modify life’s very information by replacing, inactivating, or repairing missing or faulty genes and thereby cure patients. However, the road to today’s small number of authorized gene therapies, which include treatments for disorders such as severe combined immunodeficiency syndrome, or SCID, some blood malignancies, and spinal muscular atrophy, has been difficult. Early clinical studies in the 1990s were ineffective, and the 2000s brought with them unforeseen and often fatal complications, such as a leukemia-like sickness.
Despite gene therapy’s challenges, many researchers believe sickle cell is a good target because the molecular pathways are well understood and straightforward. What’s more, every copy of the gene doesn’t need to be mended to have an effect. (Individuals who inherit the mutated gene from only one parent, for example, don’t develop sickle cell disease.)
Esrick is co-leading a clinical trial that is exploring a gene therapy to induce the body to create more of fetal hemoglobin, a healthy type of hemoglobin produced by fetuses and young babies but not adults. A virus delivers DNA for the production of a small string of genetic material known as a microRNA into cells from a patient’s bone marrow. The virus, known as a vector, permanently inserts the DNA into the genetic design of the cell. The microRNA then interferes with the creation of a protein that hinders the formation of fetal hemoglobin. When that protein is inhibited, fetal hemoglobin synthesis resumes. Like turning on a faucet, a steady stream of the healthy hemoglobin can flow into the bloodstream, making up for the faulty form.
Esrick and colleagues revealed in the New England Journal of Medicine that preliminary results released in January 2021 showed that the medication assisted six sickle cell patients in producing fetal hemoglobin. The patients’ symptoms were reduced or eradicated during the follow-up period, which ranged from few months to more than two years. The trial has been expanded to include more patients and to further examine the medication.
Scientists are also experimenting with gene therapy to combat sickle cell disease. Bluebird Bio, a biotechnology startup, is testing a method for delivering a functional copy of the HBB gene to patients. Another group is preparing to launch a study in which that gene will be edited directly using CRISPR/Cas9.
