La susceptibilité génétique chez l'être humain aux maladies infectieuses


Donald Vinh

Institut de recherche du Centre universitaire de santé McGill


Domaine : maladies infectieuses et immunitaires

Programme Chercheurs-boursiers cliniciens - Junior 2

Concours 2018-2019

A fundamental enigma in medicine is why some individuals are highly susceptible to infections, while others are not. Increasingly, many of these "medical mysteries" are found to have an underlying Primary Immunodeficiency disorder (PID). PID are genetic disorders of the immune system. The immune system is the body's army for fighting infections. Some individuals have a defect (called a "mutation") in a gene of their immune system, which prevents it from being able to defend the body. As a result, this "hole" in the immune system allows microbes to cause infections. Although each PID is rare (affecting less than 1 in 2000 people), PIDs collectively affect 1-2% of the population. Because they are rare, they are under-recognized, and affected individuals may be debilitated by severe or unexplained symptoms.

My research program investigates patients who are highly susceptible to infections to determine if they have an underlying PID. We combine clinical and laboratory expertise in infections, genetics and immunology to identify PID. This program has been gratefully supported to date by FRQS Chercheur-boursier clinicien Junior 1.

In this next phase, my research program will focus on understanding the genetic basis of two infections: a fungal disease (involving the gene, CARD9), and C. difficile-associated diarrhea. Additionally, we will continue defining two new genetic diseases of the immune system that we have discovered, both causing a "combined immunodeficiency" syndrome. Lastly, I lead a multi-center team to enable genomic-testing for PID patients across Canada.

By identifying the mechanisms through which faulty genes weaken a patient's immune system, we aim to develop new therapies to strengthen it and treat their infections. These new therapies can ultimately be used to treat others with the same infection, even if it is not genetic, such that a substantial number of patients can benefit from studying these rare disorders.