Post hoc analyses demonstrated a significantly greater putamenal TH-ir fibres in subjects with MMD (P < 0.001), MMD-LB (P < 0.001) and PD (P < 0.001) compared with the NMD group, but there was no difference among MMD, MMD-LB and PD groups (P > 0.05) These results reveal that, following the comprehensive loss of thin TH-ir putamenal fibres, some thick TH-ir fibres remained in subjects with MMD, MMD-LB and PD. The gene discussed is TH; the disease is Parkinson disease.