An international research team, led by Dr. Erwin Schurr and Dr. Thomas Hudson, Scientists at the Research Institute of the McGill University Health Centre, have identified a gene on human chromosome 6 that makes people vulnerable to leprosy. The study will be published in the March 2003 issue of Nature Genetics.
"This discovery will now allow us to study how the gene works and how it influences the infectious process. This is an important step toward the development of innovative prevention and treatment strategies for leprosy", stated Dr. Schurr.
"Leprosy has plagued humans for many centuries and it continues to be a concern in many countries," stated Dr. Marcel Behr, Infectious Disease Specialist at the MUHC and Assistant Professor of Medicine at McGill University. "These studies lead the way to developing better treatment and a possible vaccine."
Leprosy, a chronic disease caused by infection with the bacteria Mycobacterium leprae, affects approximately one million people worldwide. While it is a rare disease in Canada and the United States, the World Health Organization has identified 91 countries in which leprosy infection is highly prevalent. Symptoms of leprosy include pigmented skin lesions, permanent nerve damage leading to numbness of the feet and hands and, if left untreated, the disease may result in gross disfiguration including loss of finger, toes, feet and hands. The leprosy bacteria are transmitted through direct personal contact or contaminated respiratory droplets.
Schurr and his colleagues used a technique called "genome scanning" to map the gene. The research team analyzed DNA samples from nearly 100 families who were susceptible to the disease, and found that the families shared a common gene variant on chromosome 6. They then analyzed the DNA of an additional 200 families with leprosy to confirm their findings. "In the last few years advances in technology have made complex genetic analyses, such as those used in this study, possible, "stated Dr. Thomas Hudson. "Without these advances and the cooperation of the families, this research would not have been possible."
This is the second study, published in 2003 by McGill/CGDN scientists, that illustrates the importance of host genes in infectious disease. Dr. Philippe Gros discovered a gene (Naip-5) could make mice resistant to Legionnaire's Disease. "We are now looking forward to applying the same gene identification strategies for other common infectious diseases such as tuberculosis and malaria", stated Dr. Alexandre Alcaïs, a scientist at the Institut National de la Santé et de la Recherche Médical (INSERM) Unité 550 at Necker Medical School, Paris, and co-author of the study.
Dr. Erwin Schurr is a Scientist at the McGill Centre for the Study of Host Resistance, a Researcher at the McGill University Health Centre, and an Investigator of the Canadian Genetic Diseases Network. Dr. Thomas Hudson is Director of the Genome Quebec Innovation Centre, a Scientist at the McGill University Health Centre, and an Investigator of the Canadian Genetic Diseases Network. The research was supported with grants from the Canadian Genetic Diseases Network, Canadian Institutes of Health Research, and Genome Quebec.
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.