Czech scientists help locate gene responsible for crippling disease

DNA

Czech scientists have helped to identify a gene responsible for a debilitating hereditary disease. Charcot-Marie-Tooth or CMT disease is an inherited neurological disorder. Doctor Radim Mazanec from the Motol Teaching Hospital in Prague took part in the pioneering work.

"The CMT neuropathy is a disease of peripheral nerves and the typical clinical features of this disease are muscle weakness, especially at the leg, at the peroneal muscles and calf muscles so the people have problems with gait, and during that disease foot deformities develop, the typical ones are a high arch and hammer toes."

A few years ago Blanka Klouzalova, a woman from a small village in North Moravia saw a TV documentary about a man suffering from the CMT disorder and gradually losing control of his limbs. She realised that herself and her two children had similar symptoms.

"This lady recognised that in her village there were more people who had a problem with gait, who had foot deformities and leg weakness. She contacted us at that time with a question: 'Me and my family are suffering from very similar problems as you mentioned in your TV programme and I would like to know what is going on.' We invited her and her family to our teaching hospital in Motol in Prague for detailed examination."

At the same time a research team from the University of Antwerp in Belgium were examining a large Belgian family whose members had been known to suffer from the same disease for five generations. The Prague team decided to carry out a wider study with Mrs Klouzalova's family. Doctor Mazanec again.

"We made a very important decision to see all the family members in North Moravia and we drove there with other colleagues from our hospital, especially with Pavel Seeman, and performed examinations and we took blood samples for DNA analysis. When we returned to Prague, we sent these blood samples to our colleagues to Belgium. It was a very important moment because they were prepared to perform a detailed DNA analysis to recognise the gene which is responsible for this neuropathy."

The Belgian doctors had a vague idea of where the gene may be, but did not have enough genetic material to pinpoint the mutation. Thanks to the number of samples submitted by the Czech team, the faulty gene was identified on the 12th chromosome. Doctor Mazanec says the discovery now brings hope to future generations of potential CMT sufferers.

"Now we are able to provide genetic counselling, that is very important for the next generation. We are able to say whether the child will be healthy or sick. And very important for all medicine in the world is that we are now able to better understand the mechanism of this disease. I expect in the next 10 or 15 years we will be able thanks to a lot of experiments on animals and tissue cultures to find how to repair this gene defect. It will be for us and especially for our patients very important to help them. Not only a little bit but really we could be able to treat the cause of this very severe neurological disease."

The Czech C-M-T Society, founded in 1999, provides assistance and information to CMT patients and their families. www.websiska.cz/c-m-t