Mitochondrial disease

Gene: TK2

Green List (high evidence)

Mitochondrial DNA depletion syndrome-2 is an autosomal recessive disorder characterized primarily by childhood onset of muscle weakness associated with depletion of mtDNA in skeletal muscle. A wide clinical spectrum phenotype includes a severe, rapidly progressive, early onset form (median survival: < 2 years); a less severe childhood-onset form; and a late-onset form with a variably slower rate of progression. Clinical presentation typically includes progressive weakness of limb, neck, facial, oropharyngeal, and respiratory muscle, whereas limb myopathy with ptosis, ophthalmoparesis, and respiratory involvement is more common in the late-onset form.

Multiple families reported.

One family reported with PEO: likely represents a spectrum for mito disease.

Created: 31 Mar 2022, 7:56 p.m. | Last Modified: 31 Mar 2022, 7:56 p.m.

Panel Version: 0.758

Mode of inheritance
BIALLELIC, autosomal or pseudoautosomal

Phenotypes
Mitochondrial DNA depletion syndrome 2 (myopathic type), MIM# 609560; Progressive external ophthalmoplegia with mitochondrial DNA deletions, autosomal recessive 3, MIM# 617069

Publications

• 11687801
• 12391347
• 12873860
• 35286480
• 35280287
• 35094997