Consistent with the PI lipids influencing transporter activity, a mutation of Tyr715, which is located near the PI3P-binding site, to cysteine was recently identified in the gene encoding human CLC-7 that causes a novel lipid storage disease without osteopetrosis (Undiagnosed Diseases Network et al., 2019). The gene discussed is CLCN7; the disease is Lipid storage disease.