Monday, December 04, 2006

CF Gene Therapy Trial

The Sunday Times has an article on a new gene therapy trial for Cystic Fibrosis in the UK. Here are some excerpts:

BRITISH researchers are to trial a new gene therapy for cystic fibrosis in which sufferers simply inhale a spray laden with DNA.

....If it works, the £20m programme could lead to a treatment that will improve and extend the lives of thousands of cystic fibrosis sufferers around the world.

....About 10,000 people in Britain have cystic fibrosis. Most can expect to live no more than 31 years and much of their life will be spent struggling to control the symptoms, which can include liver failure and diabetes. Researchers emphasise that such trials must be treated and publicised with caution for fear of raising false hopes among sufferers. It will also take at least three years for the early results to emerge. However, the large-scale medical trials follow studies in animals and smaller trials in humans that have already hinted at powerful benefits.

....The technique being tested involves the use of a nebuliser that injects a fine spray into the airways. Within the spray are tiny soap-like bubbles called liposomes containing DNA without the cystic fibrosis defect. The liposomes fuse with the outer surfaces of cells lining the lungs and the DNA passes by natural processes into their nuclei. Once installed, it is hoped the DNA will prompt the cells to make the essential protein lacking in cystic fibrosis sufferers.

You can learn more about CF from the Cystic Fibrosis Foundation website and CF Trust site. Below is some useful information from the former's webpage:

What is cystic fibrosis?
Cystic fibrosis (CF) is a life-threatening disease that causes mucus to build up and clog some of the organs in the body, particularly in the lungs and pancreas. When mucus clogs the lungs, it can make breathing very difficult. The thick mucus also causes bacteria (or germs) to get stuck in the airways, which causes inflammation (or swelling) and infections that leads to lung damage.

Mucus also can block the digestive tract and pancreas. The mucus stops digestive enzymes from getting to the intestines. The body needs these enzymes to break down food, which provides important nutrients to help us grow and stay healthy. People with cystic fibrosis often need to replace these enzymes with capsules they take with their meals and snacks to help digest the food and get the proper nutrition.

How do people get cystic fibrosis?
Cystic fibrosis is a genetic disease. That means people inherit it from their parents through genes (or DNA), which also determine a lot of other characteristics including height, hair color and eye color. Genes, found in the nucleus of all the body's cells, control cell function by serving as the blueprint for the production of proteins.

The defective gene that is responsible for causing cystic fibrosis is on chromosome 7. To have cystic fibrosis, a person must inherit two copies of the defective CF gene—one copy from each parent. If both parents are carriers of the CF gene (i.e., they each have one copy of the defective gene), their child will have a 25% chance of inheriting both defective copies and having cystic fibrosis, a 50% chance of inheriting one defective copy and being a carrier, and a 25% chance of not having CF or carrying the gene.