XK protein is expressed in a number of tissues including CNS and blood cells (Russo et al., 2000; Claperon et al., 2007), and mutations within XK protein are associated with McLeod syndrome, which is characterized as a multisystem disorder with numerous abnormalities in the neuromuscular and hematopoietic systems (Ho et al., 1994; Arnaud et al., 2009; Dubielecka et al., 2011; Zhu et al., 2014). Here, XK is linked to McLeod neuroacanthocytosis syndrome.