A later large cohort study on 236 PD and 49 DLB patients enriched for different mutations in GBA, parkin, PINK1, DJ1, and LRRK2 genes [125] found positive RT-QuIC outcomes only in patients carrying GBA (93%), LRRK2 (78%), or heterozygous mutations in recessive genes (59%), while all biallelic mutation carriers remained negative. The gene discussed is GBA1; the disease is Parkinson disease.