However, the disease burden of Parkinson’s disease depends not only on motor symptoms but also, to a large extent, on non-motor symptoms (e.g. impairments in cognition or dementia).2 Currently, effective treatments for non-motor symptoms, such as cognitive deficits, are limited to cognitive3 and physical training4,5 in mild cognitive impairment and rivastigmine,6 an acetylcholinesterase inhibitor in Parkinson’s disease dementia. This evidence concerns the gene ACHE and dementia.