One particularly severe form of EB , recessive dystrophic EB ( RDEB ), is especially challenging to treat . RDEB is caused by a deficiency in type VII collagen ( C7 ), which is responsible for properly connecting the skin ’ s two main layers at the dermal-epidermal junction . In addition to severe wounds , blistering and scarring , patients experience malnutrition , anemia , esophageal strictures , dental problems , and fusion of the fingers and toes due to chronic scarring . These wounds predispose patients to infections , and they can develop into aggressive squamous cell carcinomas in adolescents and adults — a major cause of death among these patients . But there are two very promising therapies on the horizon : focal gene therapy and protein replacement therapy .
FOCAL GENE THERAPY
Ever since gene therapy was deemed both safe and effective ( 1 ), it has been widely viewed as the best option to correct the manifestations of RDEB over the long term . Since an absence or deficiency of C7 is the hallmark of RDEB , focal gene therapies rely on the restoration of C7 to improve the structural and functional