Leber Hereditary Optic Neuropathy (LHON)

Inheritance Pattern

 * Mitochondrial

Gene

 * Complex I Subunit Genes
 * ND1
 * ND4
 * ND6

Mutations

 * Three common mutations make up 90%
 * m.11778G>A (ND4) = severe, poorest prognosis
 * m.14484T>C (ND6) = best prognosis with occasional visual recovery
 * m.3460G>A (ND1) = intermediate

Penetrance

 * Homoplasmic in 85-90% of cases
 * Reduced penetrance among females
 * 50% of males will develop vision loss
 * 10% of females will develop vision loss

Features
Ophthalmology Cardiology Neurology
 * Loss of visual acuity
 * Arrhythmia
 * Tremor
 * Peripheral Neuropathy
 * Myopathy
 * Movement Disorder

Management

 * Cardiology
 * Ophthalmology
 * Neurology
 * Avoid mitochondrial toxins