LRRK2 expression linked to dopamine-innervated areas

Objective : Leucine-rich repeat kinase 2 (LRRK2) has been linked to Parkinson's disease. Our study explores the expression of LRRK2 in human and rodent brain tissue. Methods: We analyzed LRRK2 gene activity at the cellular level using in situ hybridization. Results. We found a high and strikingly specific expression of LRRK2 mRNA in rodent striatum and parts of cortex and no signals in dopamine neurons. In human tissue, LRRK2 mRNA was found in the corresponding brain areas caudatus and putamen at lower levels and dopamine neurons were also devoid of LRRK2 mRNA. Expression levels in striatal tissue did not differ between Parkinson's disease patients and control subjects. Interpretation : Unlike all other genes so far linked to Parkinson's disease, our results demonstrate that LRRK2 expression is particularly high in brain dopaminoceptive areas.