Abstract
Background: PARK8 is the most common known mendelian form of Parkinson's Disease (PD). It is due to mutations in the leucine-rich repeat kinase 2 (LRRK2) gene and G2019S is considered the most frequent mutation in the Caucasian population, in particular in the Southern Europe and Mediterranean countries. Objective: We assessed the frequency of the G2019S and R1441C/H/G mutations in 513 (311 M and 202 F) unrelated PD patients from Campania, in Southern Italy. Methods: Three hundreds and thirty-six patients presented a sporadic disease, and 177 had a familial history of PD or tremor. Three hundreds and eighty cases originated from the province of Naples. We compared our LRRK2 mutation carriers to idiopathic PD patients matched for recruiting center, gender, age and age at onset. Results: Thirteen patients (8 M and 5 F) carried the R1441C mutation and 4 (3 M and 1 F) the G2019S mutation, all in heterozygous state. All carriers originated from the province of Naples. No carriers of the R1441H or R1441G mutations were found. The LRRK2 mutation carriers were clinically similar to idiopathic PD patients. The R1441C and G2019S mutations are not rare causes of PD in Campania, especially in the province of Naples and among the familial cases, where the overall mutation prevalence is 6.8%. Conclusions: The R1441C prevalence was higher than that of G2019S (2.5% vs 0.8%), underlining the importance of the geographical differencies in LRRK2 mutation frequency for molecular screening and genetic counseling of PD patients.