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progressive external ophthalmoplegia with mitochondrial DNA deletions autosomal dominant type 4 (PEOA4)

Defects in POLG2 are the cause of progressive external ophthalmoplegia with mitochondrial DNA deletions autosomal dominant type 4 (PEOA4). Progressive external ophthalmoplegia is 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. 

ABREVIATION(S):
PEOA4

TYPE: deafness (hearing impairment), eye or vision problem

Related patway(s): DNA replication

DNAtraffic protein(s) related to disease: POLG2

OMIM: 610131

Last modification date: Oct. 19, 2011