Since REMS-active MCH neurons regulate hippocampus-dependent forgetting of contextual fear-related memories (Izawa et al., 2019), PrRP may influence the development of stress-related mental disorders associated with hippocampal dysfunction by modulating MCH activity (Cominski et al., 2014; Wingenfeld and Wolf, 2014). The gene discussed is PRLH; the disease is mental disorder.