MAPT and red-green color blindness: Under pathological conditions, tau aggregates into neurofibrillary tangles (NFTs), impairing brain function and leading to progressive neurodegeneration, a defining feature of the group of neurological disorders known as tauopathies, which includes familial frontotemporal lobar degeneration (FTLD), progressive supranuclear palsy (PSP) and corticobasal degeneration (CBD), as well as other disorders that involve tau pathology [5].