Scientists have reported that a gene responsible for hereditary deafness may play a role in wound healing and increasing protection from infection. The gene, called Cx26, was first identified by David Kelsell of Queen Mary, University of London ten years ago. The mutated form, two copies of which confers hereditary deafness, is found in populations from Africa to Asia and throughout Europe. Mutated genes with a high incidence are frequently associated with conferring an evolutionary benefit. Kelsell's team reasoned that any benefit was likely to be general not specific due to the wide geographic spread of the mutation. They investigated skin because mutant Cx26 protein sometimes causes skin disease and because skin is a very general protector against many types of pathogen.
The research, reported by team member Stella Man at the European Society of Human Genetics meeting in Amsterdam, looked at the function of proteins called connexins, which regulate the opening and closing of channels called gap junctions. Gap junctions are a primary way in which cells communicate with each other and Cx26 is a member of this connexin family. When the scientists added a mutant form of Cx26 to laboratory skin cells and introduced an aggressive bacteria called Shigella to the cultures, cells containing the mutant gene were found to be invaded by fewer bacteria. They also found that the cells carrying the mutation were able to move more rapidly in the Petri dish, a characteristic of cells involved in wound healing.
The discovery may have implications for pharmaceutical development of new drugs to aid healing after surgery, for instance by knocking out a non-mutated copy of the Cx26 protein locally around a wound site. The team will continue its investigation by looking at the effect of the Cx26 mutation in other cell types, and is particularly interested in its effect on the gut lining where defence against infection is very important.