refers to a group of genetic disorders that are characterized by misshapen, spiny red blood cells (acanthocytosis) and neurological abnormalities, especially movement disorders. The onset, severity and specific physical findings vary depending upon the specific type of NA present. Signs and symptoms usually include chorea (involuntary, dance-like movements), involuntary movements of the face and tongue, progressive cognitive impairment, muscle weakness, seizures and behavioral or personality changes. NA syndromes typically progress to cause serious, disabling complications and are usually fatal. NA is inherited, but the disease-causing gene and inheritance pattern varies for each type. Although there is some disagreement in the medical literature about what disorders should be classified as forms of NA, four distinct disorders are usually classified as the "core" NA syndromes - chorea-acanthocytosis, McLeod syndrome, Huntington's disease-like 2 and pantothenate kinase-associated neurodegeneration (PKAN). Source: Genetic and Rare Diseases Information Center (GARD), supported by ORDR-NCATS and NHGRI.