LRRK2 and Parkinson disease: All PD-associated mutations identified until now are single nucleotide substitutions, the most relevant being G2019S, which accounts for approximately half of LRRK2 mutation in Caucasian populations, underlying approximately 5% of PD cases of autosomal dominant PD and approximately 2% of PD cases with no known family history [6,7,8], and R1441C/G/H.