The antioxidant genes of glutathione peroxidase GPx1 and GPx2 are overexpressed in a cell model of mutant htt, suppressing htt103Q toxicity and decreasing caspase (a protease enzyme family with an essential role in inflammation and programmed cell death) activity; whereas mGPx1 provides neuroprotection in the eyes of HD flies and restores decreased locomotor activity and circadian arrhythmia in a Drosophila HD model. The gene discussed is GPX2; the disease is Huntington disease.