The GAM is a spongy material made from cow collegen and containing mobile pieces of DNA, called plasmids, that contain a gene that promotes bone growth. The scientists, from the biotechnology firm Selective Genetics in San Diego inserted a GAM into the broken bones of three dogs and measured the bone density by X-ray. Two to six weeks after implantation there was an increase in new bone formation at the fracture site. The technique overcomes many of the stumbling blocks normally associated with gene therapy. Because the plasmid cannot leak out of the sponge pores the gene is restricted to the site where it is needed.
Plasmids are also safer and cheaper than other vehicles for gene delivery, such as viruses.
A total of 70,000 Britons suffer osteoporotic hip fractures each year. 940m a year. The BBC is not responsible for the content of external internet sites.