LRRK2 G2019S as a Cause of Parkinson's Disease in Ashkenazi Jews

To the Editor: Most cases of Parkinson's disease are considered sporadic and idiopathic, although there is evidence of familial aggregation, and several monogenic forms have been identified. 1 Recently, several pathogenic mutations in the highly conserved leucine-rich repeat kinase 2 gene ( LRRK2 ) have been associated with autosomal dominant, late-onset Parkinson's disease. 1 Of these, the G2019S substitution is the most frequently reported. 2 It occurs in about 1 percent of unselected cases and 3 to 6 percent of familial cases of Parkinson's disease in persons primarily of European ancestry 2 but in 7 of 17 cases of familial disease in persons from . . .