Recent studies on inositol investigated the role of SYNJ1, an autosomal recessive form of early-onset parkinsonism.51 SYNJ1 is a lipid phosphatase of phosphatidylinositol-34,5-trisphosphate (PIP3).52 SYNJ1 knockout cell models were associated with an increase of α-synuclein and PIP3 levels. Here, SYNJ1 is linked to Parkinson disease.