<unk>  is a group of genetically diverse conditions complicated by movement disorders, neurological problems and spiculated (misshapen) red blood cells.  These syndromes, which include chorea acanthocytosis, McLeod syndrome, Huntington’s disease–like 2 (HDL2), and
pantothenate kinase-associated neurodegeneration (PKAN), primarily affect the brain and the basal ganglia. The conditions are caused by genetic mutations of several different genes including, VPS13A, XK, JPH3 and PANK2. The mutations are inherited through various genetic mechanisms.
Specific neurologic symptoms characterize these diseases. These symptoms may include: involuntary or slow movement; posture and skeletal related abnormalities; weakness; cognitive impairment; psychiatric symptoms; and other symptoms related to brain degeneration and movement difficulties. The disorders all have in common the presence of spiculated red blood cells, also known as spur cells, which are formally called acanthocytes.
The diseases are hereditary, but rare, and in some cases extremely rare, with insufficient data to draw conclusions about frequency of the mutation.  Huntington's disease-like 2 has slightly higher ethnic prevalence in South Africans and there is gender prevalence in McLeod Syndrome with males being more susceptible to the disease than females. The other two do not show any ethnic or gender bias.
Neuroacanthocytosis
Acanthocytosis
Spherocytosis
Poikilocytosis
Koilocytosis
Monocytosis
Plasmacytosis
Hyperpigmentation