[Comment] Unravelling the role of the microbiome in Parkinson's disease

Evidence for the involvement of the microbiome in Parkinson's disease continues to accumulate, contributing to an increasingly multidimensional picture of the interactions of the brain with other organs. The trillions of microorganisms—bacteria, fungi, viruses, and other microbes—that inhabit the human body, particularly those residing in the gut, are now recognised as key modulators of brain function and dysfunction. This recognition has led to the emergence of research into a distinct microbiome–gut–brain axis.