Leigh's Disease - Causes

Causes

It is an inherited disorder that usually affects infants between the age of three months and two years, but, in rare cases, teenagers and adults as well. In the case of the disease, mutations in mitochondrial DNA (mtDNA) or in nuclear DNA (gene SURF1 and some COX assembly factors) cause degradation of motor skills and eventually death.

Mitochondria are an essential organelle in eukaryotic cells. Their function is to convert the potential energy of glucose, amino acids, and fatty acids into adenosine triphosphate (ATP). Mitochondria carry their own DNA, called mitochondrial DNA . The information stored in the mtDNA is used to produce several of the enzymes essential to the production of ATP.

Disorders of oxidative phosphorylation may be caused by mutations in either mtDNA or in nuclear encoded genes. The latter account for the majority of Leigh disease, although it is not always possible to identify the specific mutation responsible for the condition in a particular individual.

Regardless of the genetic basis, the effect is that mitochondria fail or function improperly. In the case of Leigh disease, crucial cells in the brain stem and basal ganglia are affected. This causes a chronic lack of energy in the cells, which, in turn, affects the central nervous system and inhibits motor functions.