The apex appears more affected than the base,2,33 with sparing of the anterior and proximal regions.2,34 Over time, the loss becomes more diffuse, increasingly affecting the anterior and septal regions.3 As in PD, placebo-treated monkeys at 12 weeks exhibited greater loss of sympathetic innervation in the apex relative to the base and greatest regional loss in the inferior wall, as detected by both MHED PET (Fig. 1) and TH immunohistochemistry (Supplementary Figure 5). The gene discussed is TH; the disease is Parkinson disease.