Due to the fact that prior existent evidence suggested that odor identification appeared to be distinctly affected in LRRK2-PD patients (27, 43, 44), our group performed a study to assess olfactory function in PD patients using the Brief Smell Identification Test (B-SIT) and compared carriers of the G2019S and R1441G mutations in LRRK2 with non-carriers (45). The gene discussed is LRRK2; the disease is Parkinson disease.