GJA1 and Alzheimer disease: For instance, sites of enhanced Cx43 immunoreactivity have been identified in patients with Alzheimer's disease (AD) and in animal models of amyotrophic lateral sclerosis (ALS) and Parkinson's disease (PD; Provenzano et al., 2023; Maldonado et al., 2022; Seo et al., 2021).