MT-TV gene
The MT-TV gene provides instructions for a mitochondrial transfer RNA molecule essential for energy production, with mutations linked to rare neurological and muscular disorders.
Normal Function
The MT-TV gene provides instructions for making a specific form of transfer RNA (tRNA) designated as tRNAVal. This molecule is present only in mitochondria and attaches to the amino acid valine (Val), inserting it into proteins during assembly. These proteins are critical for oxidative phosphorylation, the process by which mitochondria convert oxygen and simple sugars into adenosine triphosphate (ATP), the cell's primary energy source.
Health Conditions Related to Genetic Changes
Mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes
Mutations in the MT-TV gene are a rare cause of MELAS. These mutations, such as G1642A and G1644A, reduce the amount of tRNAVal available for protein assembly, impairing the mitochondria's ability to produce energy. While the exact mechanism is not fully understood, this energy deficit leads to the characteristic features of MELAS.
Leigh syndrome
MT-TV gene mutations are a rare cause of Leigh syndrome, a progressive brain disorder. While it typically appears in infancy or early childhood, some cases do not manifest until adulthood. Symptoms include:
- Vomiting and seizures
- Delayed development
- Muscle weakness and movement problems
- Heart and kidney issues
- Difficulty breathing
Other disorders
Other MT-TV mutations have been linked to a variety of signs and symptoms primarily affecting the muscles and nervous system, including:
- Recurrent migraine headaches
- Poor coordination and learning disabilities
- Hearing loss and dementia
- Cardiomyopathy (weakening and enlargement of the heart muscle)
The clinical presentation can vary significantly, even among family members with the same genetic change.