XK and neuroacanthocytosis: The core neuroacanthocytosis syndromes, <i>i.e.</i>, chorea-acanthocytosis/VPS13A disease (ChAc) and McLeod syndrome/XK disease (MLS), are respectively due to mutations in <i>VPS13A</i> and <i>XK</i> genes and share similar manifestations including the formation of acanthocytes.