Although recent human genome-wide association studies have suggested that a gene set related to dopamine signaling is involved not only in ADHD alone but also in the comorbidity of ADHD with obesity and narcolepsy (Mota et al., 2020; Takahashi et al., 2020); in animal studies, lack of SorCS2 reportedly induces ADHD-like behavior by altering the novelty response to psychostimulants and altering the dopaminergic firing pattern of the ventral tegmental area (Olsen et al., 2021). Here, SORCS2 is linked to attention deficit-hyperactivity disorder.