University of Texas Southwestern Medical Center at Dallas have successfully tested the first gene therapy for skin cancer, using a mouse model for the disease xeroderma pigmentosum, or XP.

Humans with XP have a mutation that prevents the body from repairing DNA damaged by UV light. Mice with mutations in the gene Xpa suffer from XP and develop cancerous lesions on their skin within three weeks after UV light exposure.

In this gene therapy study, the normal version of mouse Xpa was injected into the mutant mice, using a disabled virus that infects multiple cells. UV light exposure after the injection did not cause lesions, and the skin cells surrounding the injection site were nearly identical to those of normal animals, indicating that the DNA repair mechanism had been restored by the addition of the normal Xpa gene.

University of Texas Southwestern Medical Center at Dallas news release