Medical researchers are continually on the lookout for new treatments for muscular dystrophy (MD), a group of hereditary muscle wasting diseases that in some cases, shorten life expectancy. There is currently no cure for MD and the treatments are limited to steroidal drugs, physical therapy, surgery and mobility aids to increase the sufferer’s independence.
Now, geneticists have discovered ways in which to skip over the faulty genetic code that causes MD, in order to halt the progression of the disease. This is called exon skipping.
What are Exons?
Genes are made up of two sections called exons and introns. The exons contain information with which to produce proteins that are essential to our bodies. The introns are cut out during the process of protein production, leaving only the exons.
The exons must join up like pieces of a puzzle. If an exon is missing, then the puzzle cannot be completed. The exon will not join on to the next available exon. If a section is missing, it will simply fail to create the rest of the section. Since the muscle protein dystrophin needs both ends of the protein in order to be made, this results in muscular dystrophy.
Now scientists have found a way to "skip over" the missing sections of DNA to join up the puzzle and potentially halt MD.
They can do this by putting a tiny fragment of DNA called an antisense oligonucleotide (AO) over the missing section so that the body will ignore that missing part and skip on to the next part of the DNA, creating an end in the structure that allows dystrophin to be formed.
Can Exon Skipping Help Cure MD?
It is too early to say whether exon skipping will lead to a cure for muscular dystrophy. However, a very small trial involving 19 boys with Duchenne muscular dystrophy has shown promising results. All 19 boys were given intravenous drips of the antisense oligonucleotide (AO) molecular patch over a period of 12 weeks. The boys were divided into groups and each group received a different dosage ranging from 0.5 to 20 mg.