For example, in the Parkinson’s Progression Markers Initiative, CSF α-synuclein SAA was positive in 67.5% of LRRK2 gene mutation carriers with PD (compared to 93.3% for sporadic PD), and in only 12.5% of female, normosmic LRRK2 carriers [31]. The gene discussed is LRRK2; the disease is Parkinson disease.