MedGen

An accumulation of free radical groups in the body inadequately neutralized by antioxidants, which creates a potentially unstable and damaging cellular environment linked to tissue damage. [from HPO]

A mode of inheritance that is observed for traits related to a gene encoded on the mitochondrial genome. Because the mitochondrial genome is essentially always maternally inherited, a mitochondrial condition can only be transmitted by females, although the condition can affect both sexes. The proportion of mutant mitochondria can vary (heteroplasmy). [from HPO]

Characterized by blood glucose levels that are higher than normal but not yet high enough to be classed as diabetes. Indicates a relatively high risk for the future development of diabetes. [from SNOMEDCT_US]

Progressive loss of neural cells and tissue. [from HPO]

A group of abnormalities characterized by hyperglycemia and glucose intolerance. [from HPO]

Fatty acid hydroxylase-associated neurodegeneration (FAHN) is characterized early in the disease course by central nervous system involvement including corticospinal tract involvement (spasticity), mixed movement disorder (ataxia/dystonia), and eye findings (optic atrophy, oculomotor abnormalities), and later in the disease course by progressive intellectual impairment and seizures. With disease progression, dystonia and spasticity compromise the ability to ambulate, leading to wheelchair dependence. Life expectancy is variable. FAHN is considered to be a subtype of neurodegeneration with brain iron accumulation (NBIA). [from GeneReviews]