| Disease ID | Source | Name | Description |
| 157640 | OMIM | Progressive external ophthalmoplegia with mitochondrial DNA deletions, autosomal dominant, 1 (PEOA1) | A disorder characterized by progressive weakness of ocular muscles and levator muscle of the upper eyelid. In a minority of cases, it is associated with skeletal myopathy, which predominantly involves axial or proximal muscles and which causes abnormal fatigability and even permanent muscle weakness. Ragged-red fibers and atrophy are found on muscle biopsy. A large proportion of chronic ophthalmoplegias are associated with other symptoms, leading to a multisystemic pattern of this disease. Additional symptoms are variable, and may include cataracts, hearing loss, sensory axonal neuropathy, ataxia, depression, hypogonadism, and parkinsonism. The disease is caused by variants affecting the gene represented in this entry. |
| 607459 | OMIM | Sensory ataxic neuropathy dysarthria and ophthalmoparesis (SANDO) | A systemic disorder resulting from mitochondrial dysfunction associated with mitochondrial depletion in skeletal muscle and peripheral nerve tissue. The clinical triad of symptoms consists of sensory ataxic neuropathy, dysarthria, and ophthalmoparesis. However, the phenotype varies widely, even within the same family, and can also include myopathy, seizures, and hearing loss. The disease is caused by variants affecting the gene represented in this entry. |
| 607459 | OMIM | Sensory ataxic neuropathy dysarthria and ophthalmoparesis (SANDO) | A systemic disorder resulting from mitochondrial dysfunction associated with mitochondrial depletion in skeletal muscle and peripheral nerve tissue. The clinical triad of symptoms consists of sensory ataxic neuropathy, dysarthria, and ophthalmoparesis. However, the phenotype varies widely, even within the same family, and can also include myopathy, seizures, and hearing loss. The disease is caused by variants affecting the gene represented in this entry. |
| 256000 | OMIM | Leigh syndrome (LS) | An early-onset progressive neurodegenerative disorder characterized by the presence of focal, bilateral lesions in one or more areas of the central nervous system including the brainstem, thalamus, basal ganglia, cerebellum and spinal cord. Clinical features depend on which areas of the central nervous system are involved and include subacute onset of psychomotor retardation, hypotonia, ataxia, weakness, vision loss, eye movement abnormalities, seizures, and dysphagia. The disease is caused by variants affecting the gene represented in this entry. |
| 613662 | OMIM | Mitochondrial DNA depletion syndrome 4B (MTDPS4B) | An autosomal recessive progressive multisystem disorder due to mitochondrial dysfunction. It is clinically characterized by chronic gastrointestinal dysmotility and pseudo-obstruction, cachexia, progressive external ophthalmoplegia, axonal sensory ataxic neuropathy, and muscle weakness. The disease is caused by variants affecting the gene represented in this entry. |
| 203700 | OMIM | Mitochondrial DNA depletion syndrome 4A (MTDPS4A) | An autosomal recessive hepatocerebral syndrome due to mitochondrial dysfunction. The typical course of the disease includes severe developmental delay, intractable seizures, liver failure, and death in childhood. Refractory seizures, cortical blindness, progressive liver dysfunction, and acute liver failure after exposure to valproic acid are considered diagnostic features. The neuropathological hallmarks are neuronal loss, spongiform degeneration, and astrocytosis of the visual cortex. Liver biopsy results show steatosis, often progressing to cirrhosis. The disease is caused by variants affecting the gene represented in this entry. |
| 258450 | OMIM | Progressive external ophthalmoplegia with mitochondrial DNA deletions, autosomal recessive, 1 (PEOB1) | A severe form of progressive external ophthalmoplegia, a disorder characterized by progressive weakness of ocular muscles and levator muscle of the upper eyelid. It is clinically more heterogeneous than the autosomal dominant forms. The disease is caused by variants affecting the gene represented in this entry. |