Mitochondrial Myopathies Flashcards
Leber’s hereditary optic neuropathy
Single base change
Complex I
Mitochondria partially defective in electron transport from NADH to ubiquinone
Causes blindness
Myoclonus epilepsy with ragged red fibres
Point mutation
tRNA (lysine)
Disrupts synthesis of proteins essential for OXPHOS
Skeletal muscle fibres have abnormally shaped mitochondria - clump together
Mitochondrial encephalomyopathy
Affects brain and skeletal muscle
Symptoms present in childhood
Kearns-Sayre Syndrome
5kb deletion
Onset before age 20
Dementia and retinitis pigmentosa
Diagnosis
Biochemical tests
Histology
Genetic Testing
Treatment
Occupational/physical therapy
Vitamin therapies
No specific treatment
Prevention
IVF strategy to replace defective mitochondria
Merge DNA from 2 eggs - one from mother one from healthy donor with functioning mitochondria
Mitochondria Gene Replacement (pronuclear stage)
Maternal Spindle Transfer (alternative)