LRRK2 and Parkinson disease: The frequency of reporting no family history of PD decreased within carrier groups: 0.38% (SE = 0.01%) LRRK2 p.G2019S carriers, 0.51% (SE = 0.01%) GBA1 p.N409S, 0.01% (SE = 0.002%) dual carriers, and 99.09% (SE = 0.01%) for noncarriers.