|http://ghr.nlm.nih.gov/ A service of the U.S. National Library of Medicine®|
The official name of this gene is “aspartyl-tRNA synthetase 2, mitochondrial.”
DARS2 is the gene's official symbol. The DARS2 gene is also known by other names, listed below.
The DARS2 gene provides instructions for making an enzyme called mitochondrial aspartyl-tRNA synthetase. This enzyme is important in the production (synthesis) of proteins in cellular structures called mitochondria, the energy-producing centers in cells. While most protein synthesis occurs in the fluid surrounding the nucleus (cytoplasm), some proteins are synthesized in the mitochondria.
During protein synthesis, in either the mitochondria or the cytoplasm, a type of RNA called transfer RNA (tRNA) helps assemble protein building blocks (amino acids) into a chain that forms the protein. Each tRNA carries a specific amino acid to the growing chain. Enzymes called aminoacyl-tRNA synthetases, including mitochondrial aspartyl-tRNA synthetase, attach a particular amino acid to a specific tRNA. Mitochondrial aspartyl-tRNA synthetase attaches the amino acid aspartic acid to the correct tRNA, which helps ensure that aspartic acid is added at the proper place in the mitochondrial protein.
The DARS2 gene belongs to a family of genes called aaRS (aminoacyl tRNA synthetases).
A gene family is a group of genes that share important characteristics. Classifying individual genes into families helps researchers describe how genes are related to each other. For more information, see What are gene families? (http://ghr.nlm.nih.gov/handbook/howgeneswork/genefamilies) in the Handbook.
At least 25 mutations in the DARS2 gene have been identified in people with leukoencephalopathy with brainstem and spinal cord involvement and lactate elevation (LBSL), a condition that affects the brain and spinal cord and causes difficulty walking. The most common mutation that causes this condition disrupts the way genetic information is pieced together to make a blueprint for producing the mitochondrial aspartyl-tRNA synthetase enzyme. Most copies of the blueprint are pieced together incorrectly, which prevents the enzyme from being produced. However, some copies are pieced together correctly, and a small amount of normal enzyme is made. Other mutations change single amino acids in the enzyme. This type of mutation results in decreased mitochondrial aspartyl-tRNA synthetase enzyme activity. With reduced activity, the enzyme has difficulty adding aspartic acid to the tRNA, which hinders the addition of this amino acid to mitochondrial proteins.
It is unclear how the gene mutations lead to the signs and symptoms of LBSL. Researchers do not understand why reduced activity of mitochondrial aspartyl-tRNA synthetase specifically affects certain parts of the brain and spinal cord.
Cytogenetic Location: 1q25.1
Molecular Location on chromosome 1: base pairs 173,824,580 to 173,858,543
The DARS2 gene is located on the long (q) arm of chromosome 1 at position 25.1.
More precisely, the DARS2 gene is located from base pair 173,824,580 to base pair 173,858,543 on chromosome 1.
See How do geneticists indicate the location of a gene? (http://ghr.nlm.nih.gov/handbook/howgeneswork/genelocation) in the Handbook.
You and your healthcare professional may find the following resources about DARS2 helpful.
You may also be interested in these resources, which are designed for genetics professionals and researchers.
See How are genetic conditions and genes named? (http://ghr.nlm.nih.gov/handbook/mutationsanddisorders/naming) in the Handbook.
acids ; amino acid ; aspartic acid ; brainstem ; cytoplasm ; enzyme ; gene ; lactate ; leukoencephalopathy ; ligase ; mitochondria ; mutation ; nucleus ; precursor ; protein ; RNA ; synthesis ; synthetases ; transfer RNA ; tRNA
You may find definitions for these and many other terms in the Genetics Home Reference Glossary (http://www.ghr.nlm.nih.gov/glossary).
The resources on this site should not be used as a substitute for professional medical care or advice. Users seeking information about a personal genetic disease, syndrome, or condition should consult with a qualified healthcare professional. See How can I find a genetics professional in my area? (http://ghr.nlm.nih.gov/handbook/consult/findingprofessional) in the Handbook.