Researchers at the University of Ottawa have announced a new discovery associated with a genetic form of Parkinson's. Individuals with a genetic variation in a region of DNA for leucine-rich repeat kinase-2 (or simply LRRK2) have a higher risk of developing Parkinson's, as well as leprosy, and Crohn’s disease. Why this is the case has been a mystery for a long time.

Now, the Canadian scientists have found that mice with a LRRK2 genetic variation differ in how they are able to deal with bacterial and viral infections. Curiously, mice with the LRRK2 genetic variation can handle a bacterial infection better than normal mice, but they fail to recover from certain viral infections.

Interestingly, the researchers found that this effect was most prominent in female mice in particular. In general, men are approximately 1.5 times more likely to develop Parkinson's than women, but this trend is not observed in people with LRRK2-associated Parkinson's where women have an equal chance of developing the condition.

The research also shows that LRRK2 increases inflammation, which could explain the link between Parkinson's, leprosy, and Crohn’s disease - all medical conditions associated with inflammation. There are currently inhibitors of LRRK2 that are being clinically tested for the treatment of Parkinson's. This new research suggests that some caution may be required in not reducing the levels of LRRK2 activity too low.