7-KC is elevated in brain tissues (Testa et al., 2016), cerebrospinal fluids and plasma of patients with neurological disorders such as Alzheimer’s disease (Mahalakshmi et al., 2021) and it is a biomarker of oxidative stress (Iuliano et al., 2003; Samadi et al., 2019; Seet et al., 2010). This evidence concerns the gene CALCA and Alzheimer disease.