Counterintuitive to these studies on reduced ZnT8 activity, Flannick et al. reported 12 rare SLC30A8/ZnT8 loss-of-function variants present in approximately 350 of 150,000 genotyped individuals where haploinsufficiency was observed to statistically reduce T2D risk (21). The gene discussed is SLC30A8; the disease is type 2 diabetes mellitus.