The study, carried out in 2017 by Pretegiani et al.20, compared the pattern of alteration of attributes of horizontal saccades, vertical saccades and antisaccades in PD and different forms of genetic parkinsonism, such as PARK1, PARK2, PARK6 and PARK9 inherited forms of PD, in addition to neurodegeneration with brain iron accumulation (NBI) and Gaucher Disease, among others. The gene discussed is SNCA; the disease is Parkinson disease.