SLC6A3 and Parkinson disease: Similarly, we recently performed data-driven subtyping of PD on the basis of 123I-metaiodobenzylguanidine (MIBG) cardiac scintigraphy, dopamine transporter (DAT) imaging data and disease duration data and reported that the rapidly progressive type presented diffuse cerebral atrophy and marked loss of cardiac sympathetic nerve terminals from the early stage of the disease [6].