Parkinson's disease (PD) is a chronic and progressive movement disorder. The LRRK2 G2019S mutation is the most frequent known cause of familial and sporadic Parkinson's disease. Knowledge of its frequency distribution is essential for clinical and molecular research as well as genetic counseling. The objective of this review is to assess the frequency distribution of G2019S mutation causing Parkinson’s disease in different populations including homogeneous ethnic groups or sub-groups of patients such as in Asia, Southern European such as Italy, Ashkenazi Jews, and North Africa. For comparison purposes, an article containing a critical analysis of this G2019S mutation distribution worldwide was reviewed. Results depicted a heterogeneous distribution with high frequencies in North African and Ashkenazi Jewish populations. Frequencies ranged from the no cases to 35.7% in sporadic and 42% in familial North- African Arab patients. Estimated frequencies were found to be variable, which may reflect ethnic differences and methodological inconsistencies. Hereby, it can be concluded that G2019S mutational frequency may vary amongst different ethnic races.
