WNK2 and Huntington disease: Other pathways that were enriched in the set of common genes identified as differentially expressed in both Hfe−/−× Tfr2mut mouse and NBIA brains again included pathways relating to neurodegenerative diseases (specifically Alzheimer's disease, Parkinson's disease and Huntington's disease), oxidative phosphorylation and the mitogen-activated protein kinase pathway (Supplementary Figure 1).