The article CRISPR Gene Editing Fixes Muscular Dystrophy in Dogs. Are Humans discusses scientific research led by Eric Olson (chair of molecular biology and professor at UT Southwestern Medical Center). Him and his team were able to successfully use the gene editing technology CRISPR to correct the genetic defect that is responsible for muscular dystrophy in four beagles. The beagles were bred with the disease-causing gene. Previous technology had been tested on rodents only, so this is the first time CRISPR was used to treat muscular dystrophy in a large animal. This is exciting news for anyone who has been affected by muscular dystrophy as it is one step closer to a cure for humans. The Duchenne disease is caused by mutations in the dystrophin gene. The dystrophin gene codes for a protein needed for correct muscle function. The muscles of people with this disease get weaker and weaker with time. As the age, they need to use wheelchairs to get around and often need ventilators to breathe in the final stages of the disease. People with the Duchenne disease have short live spans and usually only live to teenage years.
Olson and his team were able to correct this gene mutation in the beagles by splicing out offending sections on the gene with the use of CRISPR. The gene editing technology has the capability of cutting out sections of DNA at specific locations. In the Duchenne research, Olson said when him and his team snipped out the sections of the mutated dystrophin gene, it allowed for the gene to make enough of the correct protein for the muscles to function normally. Olson injected the CRISPR molecular scissors using two different methods. With two of the beagles, he directly injected the CRISPR into the muscle and with the other two beagles he injected the CRISPR into the bloodstream. Injecting it into the bloodstream allowed it to have a more widespread affect and travel to muscles throughout the body. Olson also loaded CRISPR onto a cold virus that was modified to seek out and splice DNA, particularly in the diaphragm and heart. The results 8 weeks after the injection were fascinating. The beagles that received systematic injections were producing healthy dystrophin protein at a rate from 3% to 90% of the normal levels. It is believed that if healthy dystrophin levels in humans with the disease is raised by 15%, their ability to function and their lives will be significantly better. In the beagles where CRISPR was injected directly into the muscles, there was an increase of healthy dystrophin protein, but only in those specific muscles it had been injected.
This study is encouraging and continuous to further develop the use of CRISPR to fight disease in humans. There are several other disease-causing gene mutations that have been spliced out of rodents using CRISPR. While there are still several questions about how safe the use of CRISPR really is, so far studies have shown greater than expected results. I believe advancements in the use of CRISPR is a huge success in the use of gene editing to cure disease. The successful results from several lab studies gives even more hope that the use of CRISPR will lead to disease treatment in the future. Knowing a family who just lost a son to the Duchenne muscular dystrophy makes this research even more relevant and exciting. It is exciting to see the advancements being made in science that will contribute hugely to the medical field in the future.