In a 20-year study of 4,000 people, it is discovered that groups of genes collectively known as HLA genes are associated with Parkinson's disease. In theory, that enables the immune system to attack infectious organisms without turning on itself - but it is not always an infallible system. The genes vary considerably between individuals. The researchers revealed that with better understanding of the link between Parkinson's disease, immunity and inflammation, it may be possible to design more effective drugs for treating the condition.
