The eradication of leprosy, one of the world's oldest and most feared diseases, may be one step closer. An international research team lead by scientists from the Research Institute of the McGill University Health Centre (MUHC) discovered that small changes in certain genes, the Parkin 2 gene and its neighbor, PACRG, result in an increased susceptibility to leprosy. Parkin 2 has also been shown to cause certain forms of Parkinson's Disease, a common neuro-degenerative disease in developed countries. These findings will be published in the February issue of the research journal Nature. The research was supported by the Canadian Genetic Diseases Network (CGDN), Canadian Institutes of Health Research (CIHR), and granting institutions in France and the Netherlands."Our results give an entirely novel view of the leprosy disease process," says MUHC molecular geneticist and James McGill Professor Dr. Erwin Schurr, one of the lead authors of the study that included scientists and physicians from Vietnam, Brazil, The Netherlands, France and Canada. "Our findings may hold the key to unravel why, despite effective drug treatment, leprosy persists in many parts of the world."
"Leprosy has plagued humans for many centuries and it continues to be a concern in many countries," says co-investigator Dr. Laurent Abel, study co-author and Research Director at Institut National de la Santé et de la Recherche Médical (INSERM) Unité 550 at Necker Medical School, Université René Descartes.
"These studies lead the way to approach the eradication of leprosy from a novel angle by taking into account the genetic constitution of people who suffer from the disease", added INSERM collaborator, Dr. Alexandre Alcaïs.
Leprosy, a chronic disease caused by the bacteria Mycobacterium leprae, affects approximately one million people worldwide. While it is a rare disease in North America, the World Health Organization has identified 91 countries in which leprosy infection is prevalent and concerns have been raised that the disease may make a comeback even in places like Canada. Symptoms of leprosy include pigmented skin lesions, permanent nerve damage leading to numbness of the feet and hands and, if left untreated, may result in gross disfiguration including loss of fingers, toes, feet and hands. The leprosy bacteria are transmitted through direct personal contact or contaminated respiratory droplets.
To arrive at their findings, Schurr and his colleagues analyzed DNA samples from nearly 200 Vietnamese families with leprosy. They found that the presence of certain forms of the Parkin 2 and PACRG genes was associated with a highly increased risk of developing the disease. These findings were confirmed in Brazilian leprosy patients demonstrating the significance of the results in the worldwide fight against leprosy.
"In the last few years, advances in technology have made complex genetic analyses such as those used in this study, possible, " stated co-investigator Dr. Thomas Hudson, Director of the McGill University and Genome Quebec Innovation Centre. "Without these advances, the clinical and epidemiological expertise of our collaborators in Vietnam and Brazil, and the support by an international top team of statistical geneticists from France, this breakthrough would not have been possible."
"Genetic approaches are again illuminating totally unexpected and important pathways leading to illness, said Dr. Michael Hayden, Scientific Director of the CGDN. "This is a very significant discovery."
About the Research Institute of the MUHC
The Research Institute the McGill University Health Centre (MUHC) located in Montreal, Quebec, is Canada's largest concentration of biomedical and health-care researchers. The institute has over 500 researchers, nearly 650 graduate and post-doctoral students and 306 laboratories devoted to research. The mission of the institute is to facilitate investigator-initiated and discovery-driven research that creates new knowledge. This research is inextricably linked to clinical programs at the MUHC, providing a bench-to-bedside-to-community continuum. The MUHC research institute is renowned as a world class research institution, that operates at the forefront of new knowledge, innovation, trends, and technologies.
About the McGill University and Genome Québec Innovation Centre
The McGill University and Genome Québec Innovation Centre is a world-class research facility for genomics and proteomics. Founded by Dr. Thomas Hudson and initially focused on complex genetic disorders such as cardiac disease and asthma, the centre has become a networking site for many research initiatives. Large-scale projects include haplotyping of the human genome (International HapMap Project) and defining the regulatory mechanisms of gene expression. High throughput technology platforms in sequencing, genotyping, DNA chips and mass spectrometry work in parallel to provide comprehensive, reliable service to investigators in Canada and worldwide. On the campus of McGill University in the heart of Montreal, the Centre acts as a vast resource of knowledge and technology to the academic, industrial and commercial sectors.
About the Canadian Genetic Diseases Network
The Canadian Genetic Diseases Network is a not-for-profit corporation, committed to advancing Canada's scientific and commercial competitiveness in genetic research, and the application of genetic discoveries to prevent, diagnose, and treat human disease. To achieve its objectives, CGDN participates in three essential activities: facilitates and funds collaborative research in human genetics across Canada; educates emerging scientists to excel in human genetic disease research; and facilitates partnerships between industry and academia to translate research discoveries into innovative therapies or diagnostic tests. CGDN is part of the Canadian Network Centres of Excellence program.
About the CIHR
CIHR is Canada's premier agency for health research. Its objective is to excel, according to internationally accepted standards of scientific excellence, in the creation of new knowledge and its translation into improved health for Canadians, more effective health services and products and a strengthened health care system.