Interestingly, the association of APOE4 has also been studied in Dementia with Lewy Bodies (DLB), an atypical parkinsonian disorder that shares significant overlapping characteristics with both AD and PDD (Tsuang et al., 2013; van der Lee et al., 2018; Shiner et al., 2021; Nasri et al., 2022; Bousiges et al., 2023; Carceles-Cordon et al., 2023). The gene discussed is APOE; the disease is parkinsonian disorder.