Intriguingly, SorCS2 selectively interacts with mutant huntingtin but not WT huntingtin, and it is mislocalized to perinuclear clusters in the striatal neurons of patients with HD and model mice, indicating that retromer affects the pathogenesis of HD by modulating SorCS2-mediated NR2A trafficking in MSNs (Ma et al., 2017). This evidence concerns the gene GRIN2A and Huntington disease.