• Français

Centre de recherche
Friday, April 30 2010

Mirror, mirror: scientists find cause of involuntary movements

Montreal, April 30, 2010Researchers have identified the genetic cause of mirror movements, where affected people are unable to move one side of the body without moving the other. For example, when trying to open and close their right hand, their left hand will unintentionally copy the movement. While mirror movements can be observed in fingers, hands, forearms, toes and feet of young children, persistence beyond the age of 10 is unusual.

The gene mutation found to cause mirror movements is called DCC (Deleted in Colorectal Carcinoma). This important discovery provides new understanding on how mirror movements happen and improve scientific knowledge concerning how the brain functions. Published in the latest edition of Science, the discovery is the collaboration of scientists from the Université de Montréal, Sainte-Justine University Hospital Research Center, Centre hospitalier de l’Université de Montréal, Institut de recherches cliniques de Montreal, Montreal Heart Institute and Jundishapour University of Medical Sciences.

“We found that all people affected with mirror movements in one large family have the same DCC mutation,” says senior author Guy Rouleau, a Université de Montréal professor, director of the Sainte-Justine University Hospital Research Center and a scientist at the CHUM Research Centre. “Our study suggests that individuals with mirror movements have a reduction in the DCC gene product, which normally tells the brain cell processes to cross from one side of the brain to the other. Simply put, DCC mutations have an impact on how the brain communicates with limbs.”

Discovery of the DCC mutation is significant, says Dr Rouleau: “Our study provides important clues as to how the human brain is made. One of the mysteries in neurology is how and why the nervous system crosses – now we have helped reveal the ‘how.’”

“This work is of broad interest because, despite the large number of studies on DCC in models such as fruit flies, worms and mice, this is the first study which indicates a role for DCC in the formation of brain cell connections in humans,” says Dr Frédéric Charron, study co-author and research unit director at the Institut de recherches cliniques de Montréal.

Sample groups from Canada and Iran
As part of the study, the research team analyzed the genes of four-generations of a French Canadian family affected by mirror movements. Another sample group included an Iranian family affected by the same condition. The genes of both families were compared to those of 538 people unaffected by mirror movements.

“Results of general and neurological examinations, as well as magnetic resonance imaging of the brain, were otherwise normal in people affected with mirror movements,” explains first author Dr Myriam Srour, a pediatric neurologist and a doctoral student at the Université de Montréal Faculty of Medicine. “Except that people affected by mirror movements had a DCC mutation, whereas people unaffected by the condition did not.”

Among study participants with mirror movements, the condition appeared during infancy or childhood and remained unchanged over time. Approximately half of participants with mirror movements were able to at least partially suppress their condition and function normally.

Partners in research
This study was funded by the Canadian Institutes of Health Research.

For information

Sylvain-Jacques Desjardins
International press attaché
Université de Montréal
514-343-7593
sylvain-jacques.desjardins@umontreal.ca

Notes

About the study
The article, “Mutations in DCC Cause Congenital Mirror Movements,” published in the journal Science, was authored by Myriam Srour, Jean-Baptiste Rivière, Marie-Pierre Dubé, Simon Girard, Patrick A. Dion, Daniel Rochefort, Pascale Hince, Sabrina Diab, Sylvain Chouinard, Hugo Théoret and Guy A. Rouleau of the Université de Montréal; Jessica M.T. Pham, Steves Morin and Frédéric Charron of the Institut de Recherches Cliniques de Montreal; Géraldine Asselin of the Montreal Heart Institute; and Naser
Sharafaddinzadeh of Jundishapour University of Medical Sciences.

Note to editors
The Université de Montréal name can be adapted to University of Montreal (never Montreal University).

On the Web

About this page
Updated on 11/17/2014
Created on 11/17/2014
Alert or send a suggestion
 

Every dollar counts!

Thank you for your generosity.

It's people like you that allow us to accelerate research and heal more children better every year and, as such, offer among the best healthcare in the world.

It's also possible to give by mail or by calling toll-free

1-888-235-DONS (3667)

Contact Us

514 345-4931

Légal

© 2006-2014 CHU Sainte-Justine.
All rights reserved.
Terms of Use, Confidentiality, Security

Avertissement

Les informations contenues dans le site « CHU Sainte-Justine » ne doivent pas être utilisées comme un substitut aux conseils d’un médecin dûment qualifié et autorisé ou d’un autre professionnel de la santé. Les informations fournies ici le sont à des fins exclusivement éducatives et informatives.

Consultez votre médecin si vous croyez être malade ou composez le 911 pour toute urgence médicale.

CHU Sainte-Justine