Original Synthetic Report: Origin of the G2019S mutation associated to Parkinson’s disease in Europeans and in North Africans

Abstract - Background: The G2019S mutation in the LRRK2 gene is associated with 1-2% of sporadic Parkinson’s disease (PD) cases. In Europe, the prevalence of G2019S in sporadic PD patients depends on the population, being relatively high in Spain and Portugal but low in northern Europe. Aim: To drawn up a European frequency map of the G2019S mutation. Material and Methods: A map of G2019S mutation isofrequences in Europe has been drawn up using the Spatial Analyst program, using the Kringing procedure. A total of 21 studies and publications on G2019S screening in European sporadic PD patients are taken in consideration in the present study. Results: This map shows a gradient of decreasing values from Iberia to peripheral countries. We have interpreted this geographic distribution of G2019S frequencies in Europe as the result of Berber and Arab invasions and expansions during the 8th century. An haplotype analysis, based on six microsatelliste markers, flanking on both sides of the 6055>A mutation, was performed in twenty G2019S carriers. A greater proportion of the short (SFH) and minimum–shared (MSH) haplotypes were found in Moroccan Berbers carriers. Conclusion: The geographical origin of the G2019S mutation is located in North Africa; Moroccan Berbers could be the initial carriers of the mutation that they have early transmitted during history.