MT-CYB and supranuclear palsy, progressive, 1: Regarding mtDNA haplogroup HV/HV0a, which was associated with less NT tau pathology in PSP cases, haplogroup HV is defined by a single missense variant rs193302980 in the cytochrome-b subunit of complex III (MT-CYB) and haplogroup HV0a is defined by a unique variant rs35788393 located adjacent to MT-CYB in the coding region for tRNA-threonine (Additional file 1: Figure S2).