Gene therapy hope for sickle cell disease
The mutation that causes sickle cell disease is a single-base defect in the human ßA-globin gene, which leads to the production of adnormal haemoglobin — the oxygen-carrying component of red blood cells. People who have two genes carrying the mutation develop sickle cell disease, a life-threatening illness. But having a single copy can help protect against malaria, meaning that the gene occurs widely in tropical regions.
A group of US, Canadian and French researchers used an HIV-based vector to insert a synthetically constructed gene — containing parts of the ßA-globin gene and the γ- globin gene — into mice with sickle cell disease. Almost all the mice expressed the protective gene for up to 10 months.
If this technique is proved safe in humans, it might be possible to start clinical trials within a few years.
Reference: Science 294, 2268 (2001)