New in gene therapy

Angina pain can be controlled using  gene therapy, scientists have found. Patients with severe heart disease who were not eligible for heart bypass operations, and who took up to 40 tablets per day for their angina, were given gene therapy straight into the heart muscles. At the end of the 12-month trial period it was found that many of the patients had stopped taking their tablets all together, were experiencing fewer angina attacks and had a 'much improved quality of life'.

The gene therapy was based on another therapy which stimulates the growth of blood vessels. It caused an excess of the protein that stimulates blood vessel growth, which countered the effects of the angina. The leader of the research, Professor Christer Sylven from Huddinge University Hospital in Sweden, is now trying to develop an easier mechanism of administering the therapy, as previous trials involved surgery to expose the heart.

Meanwhile, scientists from the US Department of Energy have used gene therapy in rats to reduce the desire to drink alcohol. In the study, which may eventually have implications upon the way alcoholism is diagnosed and treated, involved increasing protein receptors in the brain. Called D2, the protein is a receptor for dopamine, a chemical closely linked to feeling pleasure. Drinking alcohol makes the brain produce more dopamine than usual, but the receptors for it are gradually destroyed by alcohol intake. This means that someone may drink more to try to experience the same levels of pleasure.

The researchers introduced the D2 receptor gene directly into the brains of rats that had been trained to self-administer alcohol, to see if they would start producing more receptors. Levels of the receptors were shown to increase for a short period, in which the rats were studied to see if they preferred alcohol over water. All the rats showed a marked reduction in their alcohol consumption.