Mitochondria have their own DNA, which is always inherited from the mother.
However, MELAS syndrome is often not actually inherited; the mutation in this disorder commonly occurs spontaneously.
The syndrome affects all ethnic groups and both males and females.
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The disease often is fatal.
Since there is no cure for MELAS syndrome, medical care is largely supportive.
These are not truestrokes, hence the term “stroke-like.”
Other common symptoms related to encephalopathy are recurrent migraine-like headaches,seizures, vomiting, and cognitive impairment.
Patients with MELAS often have short structure and hearing loss.
In addition, myopathy (muscle disease) causes difficulty in walking, moving, eating, and speaking.
Affected individuals usually begin showing symptoms between the ages of 4 and 40.
Tests can check the level of lactic acid in the blood andcerebrospinal fluid.
Blood tests can check for an enzyme (creatine kinase) present in muscle disease.
A muscle sample (biopsy) can be tested for the most common genetic defect present in MELAS.
Moderate treadmill training can help improve the endurance of individuals with myopathy.
Metabolic therapies, including dietary supplements, have shown benefits for some individuals.
Whether these supplements will help all individuals with MELAS syndrome is still being studied.
Schon EA, Dimauro S, Hirano M.Human mitochondrial DNA: roles of inherited and somatic mutations.Nat Rev Genet.
2015;73(11):959-67. doi:10.1590/0004-282X20150154
