Furthermore, ATF6 is known as a brain biomarker for various nervous system diseases, including amyotrophic lateral sclerosis (ALS), Alzheimer’s disease (AD) [83], and neonatal hypoxic–ischemic encephalopathy [84], but whether ATF6 can be used as a biomarker of schizophrenia has not been reported. Here, ATF6 is linked to Alzheimer disease.