What is mitochondrial Encephalomyopathy?
Mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) is an extremely rare genetic condition that begins in childhood. The disorder affects many areas of the body, especially the brain and nervous system (encephalo-) and muscles (myopathy).
How common is mitochondrial Encephalomyopathy?
The exact incidence of MELAS is unknown. It is one of the more common conditions in a group known as mitochondrial diseases. Together, mitochondrial diseases occur in about 1 in 4,000 people.
What is tRNA Leu uur?
The tRNALeu(UUR) molecule is present in cellular structures called mitochondria. These structures convert energy from food into a form that cells can use. Within mitochondria, tRNALeu(UUR) is involved in the assembly of proteins that carry out a series of chemical steps called oxidative phosphorylation.
Is MELAS a mitochondrial disease?
Affected Populations MELAS syndrome is a rare disorder that affects males and females in equal numbers. Although rare, MELAS syndrome is probably the most common type of mitochondrial myopathy caused by mutations in mtDNA.
What is the life expectancy of someone with MELAS?
The prognosis for MELAS is poor. Typically, the age of death is between 10 to 35 years, although some patients may live longer. Death may come as a result of general body wasting due to progressive dementia and muscle weakness, or complications from other affected organs such as heart or kidneys.
What is the most common type of mitochondrial disease?
Together, Leigh syndrome and MELAS are the most common mitochondrial myopathies. The prognosis of Leigh syndrome is generally poor, with survival generally being a matter of months after disease onset.
What causes ragged red fibers?
This appearance is due to the accumulation of abnormal mitochondria below the plasma membrane of the muscle fiber. These may extend throughout the muscle fiber as the disease severity increases. The mitochondrial aggregates cause the contour of the muscle fiber to become irregular, causing the “ragged” appearance.
How long can you live with MELAS?
How long can you live with mitochondrial myopathy?
A small study in children with mitochondrial disease examined the patient records of 221 children with mitochondrial disease. Of these, 14% died three to nine years after diagnosis. Five patients lived less than three years, and three patients lived longer than nine years.