WNK2 and amyotrophic lateral sclerosis: Mitogen-activated protein kinase (MAPK) signaling pathways play important roles in neuronal development and function, and aberrant regulation of MAP kinases is associated with many neurological diseases, such as Parkinson’s disease (PD), amyotrophic lateral sclerosis (ALS) and Alzheimer’s disease (AD) (Thomas and Huganir, 2004; Schellino et al., 2019; Hotamisligil and Davis, 2016; Hollville et al., 2019; Asghari Adib et al., 2018).