PTC uses its alternative splicing technology to identify molecules that modulate mRNA splicing. Approximately 94% of all human genes undergo splicing. Through alternative splicing, by including or excluding exons, one gene can generate several mRNA products that can have different biological functions. Mutations that lead to alternative splicing or altered regulation of alternative splicing are the direct cause of many human diseases, including many forms of cancer, Riley-Day syndrome (familial dysautonomia), myotonic dystrophy, and spinal muscular atrophy.
PTC has developed a powerful high-throughput drug discovery technology that enables us to identify small molecule modifiers of pre-mRNA splicing. Using this technology, we have successfully identified oral small molecules that modify splicing of the Survival of Motor Neuron 2, or SMN2, gene, to increase the levels of full length SMN protein. The lack of full length SMN protein is responsible for the genetic disorder called spinal muscular atrophy. Based on the knowledge and experience from the SMA program, we believe that other small molecule drug candidates can be identified that modify alternative splicing of genes, promote inclusion of specific exons into mRNA or force skipping of undesired exons from the mature mRNA. We believe that this technology has a broad potential applicability to a large number of target genes in all therapeutic areas.