MONTREAL, June 3 /CNW Telbec/ - A MUHC-led study identifies a gene
responsible for Leber Congenital Amaurosis (LCA), the most common cause of
congenital blindness in infants and small children. The study, partly funded
by the Foundation Fighting Blindness in Canada (FFB-C), is published in
today's issue of Nature Genetics.
"This discovery has the potential to fast-track a cure for this disease,"
says lead investigator Dr. Robert Koenekoop, director of the McGill Ocular
Genetics Centre at the MUHC. "Our main research goal is to identify all the
genes responsible for congenital blindness in children and then study them so
that we can then use gene therapy to rescue their vision."
Working with an international team of researchers including Drs. Anneke
den Hollander, Frans Cremers and Ronald Roepman from the University of
Nijmegen in The Netherlands, and Dr. Chris Inglehearn from The University of
Leeds in the UK, Dr. Koenekoop and his team, including Dr. Irma Lopez, used a
new technique called SNP (single nucleotide polymorphism) technology to
identify homozygous regions in the genome, which led to the discovery of the
new gene called LCA5. In the past, large families were necessary to find
genes, but in this study only samples from one Quebec and one American patient
were used to accomplish this. The SNP micro array technology accelerated the
process of locating the gene and enabled the investigators to isolate it
within a few months instead of several years. "This method may become a model
for identifying other retinal diseases and causes of blindness in the future,"
says Dr. Koenekoop, who is also associate professor in Ophthalmology and Human
Genetics at McGill University.
The same international research team identified the CEP290 gene last
year, the most common genetic cause of LCA (American Journal of Human Genetics
September, 2006). By using the protein structure of CEP290, the investigators
were able to discover LCA5, as they have similar structures and functions in
the retina. Both the CEP290 and LCA5 genes encode proteins with vital
functions in the cilium of the photoreceptors, transporting visual proteins to
the compartment where vision occurs. When these genes are mutated, which
occurs in about 25 to 30 per cent of blind children, the visual proteins are
not transported properly to the outer segments, causing the photoreceptors to
stop working and die.
This year, after many years of research on a related LCA gene called
RPE65 and a spectacular rescue of vision by RPE65 gene replacement in dogs
with LCA, human clinical trials have started in London, UK and in
Philadelphia, USA. "Preliminary results have been very encouraging and we
expect to launch clinical trials investigating gene replacement for CEP290 and
LCA5 in the near future," says Dr. Koenekoop.
An estimated 200,000 children worldwide are afflicted with LCA.
The FRSQ, the TD FINANCIAL GROUP and The Foundation Fighting Blindness in
Canada (FFB-C) funded this research. "Discoveries like this one show us that
treatments and cures are in sight. The Foundation Fighting Blindness in Canada
is proud to fund quality vision research at the MUCH that is giving hope to
families affected by blindness," says Sharon Colle, National Executive
Director of the FFB-C.
About the McGill University Health Centre
The McGill University Health Centre (MUHC) is a comprehensive academic
health institution with an international reputation for excellence in clinical
programs, research and teaching. The MUHC is a merger of five teaching
hospitals affiliated with the Faculty of Medicine at McGill University - the
Montreal Children's, Montreal General, Royal Victoria, and Montreal
Neurological hospitals, as well as the Montreal Chest Institute. Building on
the tradition of medical leadership of the founding hospitals, the goal of the
MUHC is to provide patient care based on the most advanced knowledge in the
health care field, and to contribute to the development of new knowledge.
The Research Institute of the McGill University Health Centre (RI MUHC)
is a world-renowned biomedical and health-care hospital research centre.
Located in Montreal, Quebec, the institute is the research arm of the MUHC, a
university health center affiliated with the Faculty of Medicine at McGill
University. The institute supports over 500 researchers, nearly 1000 graduate
and post-doctoral students and operates more than 300 laboratories devoted to
a broad spectrum of fundamental and clinical research. The Research Institute
operates at the forefront of knowledge, innovation and technology and is
inextricably linked to the clinical programs of the MUHC, ensuring that
patients benefit directly from the latest research-based knowledge. For
further details visit: www.muhc.ca/research.
For further information:
For further information: Seeta Ramdass and Alex Fretier, Public
Relations & Communications Coordinators, MUHC Public Relations &
Communications Services, (514) 843-1560, (514) 531-5850