The SIGMAR1 protein functions as a subunit of the ligand regulated potassium channel, which can bind to neurosteroids, psychostimulants, and dextrobenzomorphans [103]. A mutation in SIGMAR1 gene established a connection between familial ALS with FTD to chromosome 9p13.2-21.3 [104],[105]. Here, SIGMAR1 is linked to amyotrophic lateral sclerosis.