Skuladottir et al. reported that PD onset was earlier for ITSN1 PTV carriers (mean, 57.8; standard deviation, 18.0) versus noncarriers (mean, 73.0; standard deviation, 10.3) in the deCODE cohort.7 In AMP-PD, the median age of diagnosis was 67 (n = 4; IQR, 65, 69) for ITSN1 PTV carriers versus a median of 61 (IQR, 54, 68) for the remaining cases. The gene discussed is ITSN1; the disease is Parkinson disease.