RASD2 and Huntington disease: Ras homolog enriched in the striatum (Rhes) (Falk et al., 1999) is a small GTPase that also functions as a SUMO E3 ligase to enhance SUMOylation of poly‐Q expanded mutant Huntingtin (mHTT), the protein that is the cause of the lethal neurodegenerative disorder Huntington's disease (HD) (Harrison & Lahoste, 2013).