The CRISPR genome editor has already been successfully used to treat various anomalies. And now the editors of Science Alert are reporting that CRISPR has shown its effectiveness again. This time in the treatment of Duchenne muscular dystrophy.
Duchenne muscular dystrophy (also known as Becker muscular dystrophy) is a genetic disorder associated with a mutation in the DMD gene, which encodes the dystrophin protein. The disease is linked to the X chromosome and is characterized by proximal muscle weakness caused by degeneration of muscle fibers. Such patients at an early age lose the ability to walk, and by the age of 30, most develop cardiopulmonary insufficiency, which is often the cause of death. To complicate matters further, the DMD gene consists of many "parts" (exons) that can be damaged during the formation process, which will cause a defect in the gene.
Scientists at the University of Texas, along with colleagues at the Royal Veterinary College London, have used a rather interesting approach called exon skipping. It lies in the fact that in 13% of patients, the reading of the gene can be restored by removing 51 exons. The study involved beagle dogs that have the same disease and the same gene is responsible for its development, damage to which leads to the same consequences.
Dystrophin gene restoration scheme using exon skipping or restoring its sequence.
In total, 2 experiments were carried out with the CRISPR system: in the first two puppies with an affected DMD gene, viral particles with CRISPR were injected into the gastrocnemius muscle and a control measurement was carried out after 6 weeks. It turned out that the production of dystrophin in the muscle tissue began in a total of 60% of the norm. In a second experiment, two other puppies were injected with the same particles that were injected into the muscle. After 8 weeks, the amount of dystrophin reached a concentration of up to 50% of the norm in 1 puppy and up to 90% of the norm in the second puppy.
At the same time, even in spite of such impressive results, according to scientists, therapy with CRISPR requires additional and extremely lengthy trials, because at the moment it is not clear how long the protein concentration is maintained in muscles at the required level and how it affects the body in the whole.
Vladimir Kuznetsov
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