Dofetilide is a class III antiarrhythmic agent. It is marketed under the trade name Tikosyn by Pfizer, and is available in the United States in capsules containing 125, 250, and 500 µg of dofetilide. It is not available in Europe or Australia. In the United States it is only available by mail order or through specially trained local pharmacies. Medical uses
Dofetilide is used for the maintenance of sinus rhythm in individuals prone to the occurrence of atrial fibrillation and flutter arrhythmias, and for chemical cardioversion to sinus rhythm from atrial fibrillation and flutter.Based on the results of the Danish Investigations of Arrhythmias and Mortality on Dofetilide ("DIAMOND") study, dofetilide does not affect mortality in the treatment of patients post-myocardial infarction with left ventricular dysfunction, however it was shown to decrease all-cause readmissions as well as CHF-related readmissions. Because of the results of the DIAMOND study, some physicians use dofetilide in the suppression of atrial fibrillation in individuals with LV dysfunction, however use appears limited: After initially receiving marketing approval in Europe in 1999, Pfizer voluntarily withdrew this approval in 2004 for commercial reasons and it is not registered in other first world countries. It has clinical advantages over other class III antiarrhythmics in chemical cardioversion of atrial fibrillation, and maintenance of sinus rhythm, and does not have the pulmonary or hepatotoxicity of amiodarone, however atrial fibrillation is not generally considered life-threatening, and dofetilide causes an increased rate of potentially life-threatening arrhythmias in comparison to other therapies.
Spinal muscular atrophy with progressive myoclonic epilepsy (SMA-PME), sometimes called Jankovic–Rivera syndrome, is a very rare neurodegenerative disease whose symptoms include slowly progressive muscle (atrophy), predominantly affecting proximal muscles, combined with denervation and myoclonic seizures. Only 12 known human families are described in scientific literature to have SMA-PME.SMA-PME is associated with a missense mutation (c.125C→T) or deletion in exon 2 of the ASAH1 gene and is inherited in an autosomal recessive manner. SMA-PME is closely related to a lysosomal disorder disease called Farber lipogranulomatosis. As with many genetic disorders, there is no known cure for SMA-PME. The condition was first described in 1979 by American researchers Joseph Jankovic and Victor M. Rivera. ASAH1 gene
The ASAH1 gene codes for acid ceramidase, an enzyme found in lysosomes. The lysosome breaks down acid ceramidase; the fatty acid component  is then used to produce myelin. Myelin is an insulating coating around the neurons in the body which helps to contain bioelectrical signals along a nerve cells axon and increase transmission rate. In patients with SMA-PME, the ceramidase function decreases to 33.33% effective. The lack of myelin resulting from the lack of acid ceramidase breakdown leads to nerve cell dysfunction. See also
Spinal muscular atrophies
Progressive myoclonus epilepsy

References
Further reading
National Institutes of Health (December 2013). "Genetics Home Reference: Spinal muscular atrophy with progressive myoclonic epilepsy". == External links ==