IRCM scientists identify a mutant mouse that reproduces Parkinson’s disease

Montreal, QC May 30, 2003 A group of scientists led by Dr Jacques Drouin of IRCM, in collaboration with colleagues from the Montral Neurological Institute and Centre hospitalier de l’Universit de Montral (CHUM), say they will publish the results of studies that lay the groundwork for a genetic understanding of the causes of Parkinson’s disease in the June issue of Development.

A group of neurons, known as dopaminergic neurons, are essential for motor functions. Patients afflicted with Parkinson’s disease lose some of these neurons and this causes a deficiency in dopamine and ultimately leads to movement disorders characteristic of the disease.

IRCM scientists have shown that a particular gene, named Pitx3, plays a crucial role for the survival of dopaminergic neurons. This gene is expressed in a region of the midbrain that is associated with movement control. The scientists showed that a mutation in the mouse Pitx3 gene leads to cell death of Pitx3-expressing neurons and that Pitx3-expressing neurons correspond to those that are lost in Parkinson patients. This mutation causes a greater than 90% deficiency in dopamine and leads to a loss of spontaneous movement that is similar to Parkinson’s disease.

In brief, the progressive loss of neurons leading to Parkinson’s disease has been reproduced in mice. This breakthrough opens the way to the elucidation of mechanisms leading to Parkinson’s disease and may provide opportunities for treatment by gene and cell therapy. References are available at the following address http://dev.biologists.org/cgi/content/abstract/130/11/2535

The research was funded by GlaxoSmithKline, the Canadian Institutes of Health Research and the Parkinson Society of Canada.