Today, when genetic diseases are detected, physicians can do more than just treat the symptoms. In some cases, they can actually replace defective genes with healthy ones or repair a misspelling in the DNA. These technologies are the tip of the iceberg, a preview of what will be possible in the coming years.
Genetic diseases that result from malfunctioning enzymes needed to sustain life can now be treated with enzyme replacement therapy. Using recombinant techniques, healthy enzymes can be created and then infused into patients with enzyme deficiencies resulting from their genetic disease.
Gene therapy, made possible because of growing knowledge of genomics and the development of sophisticated technology, involves fixing the underlying genetic problem, not the symptoms of the condition. Introducing a new gene to replace a defective one that is causing the problem is the basis of gene therapy. For example, replacing a defective gene in Leber congenital amaurosis, an eye disorder, has been tested in a clinical trial, and the results have been promising. Gene therapy for children with a neuromuscular disorder called spinal muscular atrophy has been approved by the Food and Drug Administration. Research is underway to see if these technologies can be used to develop treatments for other disorders.
Sources: What is gene therapy?: MedlinePlus Genetics; Gene Therapy for Leber Congenital Amaurosis Caused by RPE65 Mutations: Safety and Efficacy in 15 Children and Adults Followed Up to 3 Years | Ophthalmology | JAMA Ophthalmology | JAMA Network; FDA approves innovative gene therapy to treat pediatric patients with spinal muscular atrophy, a rare disease and leading genetic cause of infant mortality | FDA ]
RNA therapeutics have been used effectively in the clinic in a variety of ways, including to replace proteins responsible for genetic defects and as a platform for vaccines. This approach was used to develop the COVID-19 vaccines and boosters.
Sources: Recent Advances in RNA Therapy and Its Carriers to Treat the Single-Gene Neurological Disorders – PMC (nih.gov); Recent Advances in RNA Therapy and Its Carriers to Treat the Single-Gene Neurological Disorders – PMC (nih.gov) ]
The next generation of gene editing technology has enabled researchers to cure sickle cell anemia by changing a letter in the DNA sequence of red blood cells. This technique shows promise for other complex and rare diseases that have eluded treatment options.