Hallmark biochemical changes—including GSH depletion, GPX4 inactivation, and accumulation of lipid peroxides—are consistently observed in HD mouse models (e.g., R6/2, N171) and in human post-mortem tissue, accompanied by ferroptosis-related transcriptional alterations revealed by single-nucleus RNA sequencing of the HD striatum [133,134]. The gene discussed is GPX4; the disease is Huntington disease.