Exon Skipping

Genes are generally made up of exon sequences (where the As, Ts, Cs and Gs code for protein as described above) and intron sequences (where it doesn’t spell out a protein - don’t ask what it does do – it gets complicated!). The collagen gene involved with DEB (COL7A1) has over a hundred exons with introns in between. For the protein to be made, the message jumps from exon to exon and ignores the introns. If one of the exons contains a change that causes the whole protein to be broken, a type of therapy called ‘exon skipping’ can be used to make a protein that leaves out some of the exons, so is a bit shorter, but still works. This therapy has the potential to help people with EB and already been used in a different genetic condition called Duchenne Muscular Dystrophy.