SNCA and Parkinson disease: Thus, the tightly connected degeneration of the soma (represented by NRCSN) and presynaptic terminals (represented by SBR) in both PD and CBS raises the possibility of an association between the asymmetry of parkinsonism and the vulnerability of hyperbranched axons, a unique morphological feature of the nigrostriatal dopaminergic neuron [27], to pathological alpha synuclein / tau aggregation.