EARS2

Leukoencephalopathy with thalamus and brainstem involvement and high lactate

At least 23 mutations in the EARS2 gene have been found in individuals with leukoencephalopathy with thalamus and brainstem involvement and high lactate (LTBL), a condition characterized by abnormalities in certain brain regions, including the thalamus and the brainstem (the part of the brain that connects to the spinal cord), and a high level of a substance called lactate in the brain and elsewhere in the body. Affected individuals typically have problems with thinking and motor abilities and with controlling muscle function.

The EARS2 gene mutations involved in LTBL likely reduce the amount of mitochondrial glutamyl-tRNA synthetase. A shortage of this protein is thought to prevent the normal assembly of new proteins within mitochondria. Researchers speculate that impaired protein assembly disrupts mitochondrial energy production. However, it is unclear exactly how EARS2 gene mutations lead to the features of LTBL.