Advance at IRCM could pave the way for better diagnostics.
From left to right : Sabrina Schlienger, Patricia Yam et Frédéric Charron.
The team of Dr. Frédéric Charron, Director of the Molecular Biology of Neural Development Research Unit at the Clinical Research Institute of Montreal (IRCM), in collaboration with Dr. Myriam Srour of the Montreal Children's Hospital, has made a promising breakthrough in understanding the origins of Mirror Movement Disorder.
Co-authored by postdoctoral fellow Dr. Sabrina Schlienger and research associate Dr. Patricia Yam, the study was published in the prestigious journal Science Advances.
The Mirror Movement Disorder is an inherited neurological condition that is manifested through involuntary movements, primarily in the arms and hands, at an early age. In affected individuals, the right hand involuntarily reproduces the movements of the left hand and vice versa, hence the name "mirror movements". This disorder can cause pain in the arms during prolonged activities as well as difficulties in performing tasks requiring left-right coordination.
“Mirror Movement Disorder has a daily impact on the life of those affected. In fact, the simple act of buttoning one's shirt or tying one's shoelaces can be challenging as well as the practice of certain sports or music instruments such as the piano,” explains Dr. Charron, who is a Full Research Professor at the Université de Montréal and an Associate Professor at McGill University.
Over the past 30 years, scientists have identified a group of genes working together, called the Netrin signalling pathway, which is involved in the attraction of neurons connecting the left and right sides of the brain to each other, and to the spinal cord. This mechanism of neuronal guidance during embryonic development is essential for motor development.
Dr. Charron's study is based on the observation of this genetic background in a family who has carried the disease for more than four generations. The study sheds light on a new genetic mutation that causes the mirror movement disorder and incites its mechanism of action at the molecular level. Using a preclinical model, the team found that the mutation in a gene newly involved in the Netrin pathway results in abnormal movements, similar to those observed in the mirror movement syndrome.
This advance is good news for many people with this condition who, until now, did not know which mutated gene was the cause of their condition. The identification of the genes involved is an important first step towards rapid and effective diagnosis. Furthermore, understanding the mechanisms causing mirror movements is essential for the search for innovative treatments. Thus, the discovery of this mutation and its action could eventually provide promising new targets for the search for treatments for mirror movement syndrome as well as for other conditions caused by developmental defects of the nervous system.
“This is a great advance that considerably improves the state of scientific knowledge in our field of study and demonstrates the strength of combining clinical studies in human genetics with basic research," said Dr. Charron.
The article in Science Advances
Acknowledgement
This study was made possible through the support of the Canadian Institutes of Health Research (CIHR), the Neurobasis project of the Canada Foundation for Innovation (CFI), the Fonds de recherche du Québec - Santé (FRQS), and the National Institutes of Health. Frédéric Charron holds the Canada Research Chair in Developmental Neurobiology.
