ERK signalling has also been linked to neurodegenerative conditions such as Alzheimer's disease (AD), Parkinson's disease (PD) and amyotrophic lateral sclerosis (ALS) which are characterised by aberrant protein aggregation in the central nervous system (CNS), and in which neuroinflammation is commonly a hallmark of disease [103]. The gene discussed is MAPK1; the disease is Parkinson disease.