It is assumed that the other mutations, especially the splicing and frameshift mutations, also result in a drastic decrease in CaV2.1 currents, though this may not be the case for all mutations. CACNA1A is heavily expressed in Purkinje cells of the cerebellum where it is involved in coupling action potentials with neurotransmitter release. Thus, decrease in Ca2+ entry through CaV2.1 channels is expected to result in decreased output from Purkinje cells, even though they will fire at an appropriate rate. The tottering mouse is a widely used model to study EA2, as it developed a spontaneous homologous mutation in Cacna1a in the early 1960s. Alternatively, some CACNA1A mutations, such as those seen in familial hemiplegic migraine type-1, result in increased Ca2+ entry and, thereby, aberrant transmitter release. This can also result in excitotoxicity, as may occur in some cases of spinocerebellar ataxia type-6. EA3: 1q42
Episodic ataxia type-3 (EA3) is similar to EA1 but often also presents with tinnitus and vertigo. Patients typically present with bouts of ataxia lasting less than 30 minutes and occurring once or twice daily. During attacks, they also have vertigo, nausea, vomiting, tinnitus and diplopia. These attacks are sometimes accompanied by headaches and precipitated by stress, fatigue, movement and arousal after sleep. Attacks generally begin in early childhood and last throughout the patients lifetime. Acetazolamide administration has proved successful in some patients. As EA3 is extremely rare, there is currently no known causative gene. The locus for this disorder has been mapped to the long arm of chromosome 1 (1q42).
Classified may refer to:

General
Classified information, material that a government body deems to be sensitive
Classified advertising or "classifieds"

Music
Classified (rapper) (born 1977), Canadian rapper
The Classified, a 1980s American rock band featuring Steve Vai
Classified Records, an American record label

Albums
Classified (Bond album), 2004
Classified (Classified album), 2013
Classified (Sweetbox album), 2001
Classified, by James Booker, 1982

Songs
"Classified", by C. W. McCall from Wolf Creek Pass, 1975
"Classified", by the Orb from Metallic Spheres, 2010
"Classified", by Pete Townshend from the compilation Glastonbury Fayre, 1972
"Classifieds", by the Academy Is... from Almost Here, 2005

Other media
Classified (1925 film), an American silent film
Classified: The Edward Snowden Story, a 2014 Canadian film
Classified: The Sentinel Crisis, a 2005 video game for the Xbox

See also
Classification (disambiguation)
Classifier (disambiguation)