Researchers from the Guy Rouleau Laboratory affiliated with the CHUM Research Centre and the CHU-Sainte-Justine Research Centre have discovered the genetic cause of a rare disease reported only in patients originating from Newfoundland: hereditary spastic ataxia (HSA).
This condition is characterized by lower-limb spasticity (or stiffness) and ataxia (lack of coordination), the latter leading to speech and swallowing problems, and eye movement abnormalities. The disease is not deadly, but people start developing gait problems between 10 to 20 years of age, walk with a cane in their 30s, and in the most severe cases, are wheel-chair bound in their 50s. It has been shown that HSA is transmitted from the affected parent to the child in a dominant fashion, which means there is a 50% chance of the child having the mutation.
History of a discovery: collaboration between the University of Montreal and Memorial University
Researchers and clinicians from Memorial University (St. John's, Newfoundland) contacted Dr. Rouleau, who is also a professor of medicine at the University of Montreal, over a decade ago to investigate the genetics behind this disorder occurring in three large Newfoundland families. Dr. Inge Meijer, a former doctoral candidate in the Rouleau Laboratory, discovered that these families were ancestrally related, and in 2002, identified the locus (DNA region) containing the mutation causing HSA.