Mitochondrial disease

Gene: IBA57

Green List (high evidence)

More than 15 families reported with bi-allelic variants in this gene and a severe neurodegenerative disorder characterised by loss of previously acquired developmental milestones in the first months or years of life. Some affected individuals have normal development in early infancy before the onset of symptoms, whereas others show delays from birth. Features included loss of motor function, spasticity, pyramidal signs, loss of speech, and cognitive impairment. The disease course is highly variable: some individuals die of respiratory failure early in childhood, whereas some survive but may be bedridden with a feeding tube. Less commonly, some individuals may survive and have a stable course with motor deficits and mild or even absent cognitive impairment, although there may be fluctuating symptoms, often in response to infection. Other variable features include visual problems and seizures. Brain imaging shows diffuse leukodystrophy in the subcortical region, brainstem, cerebellum, and spinal cord. Laboratory studies tend to show increased lactate and CSF glycine, and decreased activity of mitochondrial complexes I and II, although these findings are also variable.

Created: 21 Sep 2020, 10:18 a.m. | Last Modified: 21 Sep 2020, 10:18 a.m.

Panel Version: 0.498

Mode of inheritance
BIALLELIC, autosomal or pseudoautosomal

Phenotypes
Multiple mitochondrial dysfunctions syndrome 3, MIM# 615330

Publications

• 23462291
• 25971455
• 27785568
• 28671726
• 28913435