SIGMAR1 and early-onset autosomal dominant Alzheimer disease: Sigmar1 has been extensively studied in the central nervous system, and the association of SIGMAR1 gene mutation has been demonstrated in numerous neurodegenerative diseases, such as, Parkinson’s disease, Alzheimer’s disease, Huntington’s disease, silver-like syndrome, amyotrophic lateral sclerosis, and certain psychiatric disorders (Mishina et al., 2005; Mishina et al., 2008; Aishwarya et al., 2021).