Indeed, several studies have reported the dual role of ERK1/2 signaling, as a double-edged sword [34], that in response to specific signals may lead to beneficial effects on long-term and short-term memory formation and neuronal protective activity in Huntington’s disease models (HD) [35,36] and to detrimental effects that induce neurotoxicity [37]. The gene discussed is MAPK3; the disease is Huntington disease.