Previous studies in idiopathic Parkinson’s disease (iPD) have shown a reduction in the substantia nigra (SN) area hyperintense in Neuromelanin-sensitive MR images (NM-MRI). However, a few genetic mutations have been associated to PD. In this study we compared images obtained in iPD and in patients with LRRK2 or GBA mutations. Images were also acquired in control subjects. The area and contrast-ratio of SN in NM-MRI and the relative midbrain volumes were evaluated. There were no significant differences in volumes, but the SN area in NM-MRI accurately differentiated LRRK2 PD patients from controls. No differences were found between PD groups.