Research is also being conducted on gene therapies, such as AAV-GRN (adeno-associated viral progranulin), and the correction of GRN mutations using CRISPR-Cas9 (clustered regularly-interspaced short palindromic repeats-associated protein 9), particularly in the context of frontotemporal dementia (FTD) (Raitano et al., 2015; Arrant et al., 2018; Amado et al., 2019). The gene discussed is GRN; the disease is frontotemporal dementia.