Leber Hereditary Optic Neuropathy

Leber Hereditary Optic Neuropathy (LHON) is the most common inherited mitochondrial disorder.

It is caused by a mutation in mitochondrial DNA, which means that the disease is transmitted maternally. Since each mitochondrion has it’s own genome, the mutation may only affect some of the mitochondria. The variable organelle genome is called heteroplasmy, which is responsible for the variable expressivity seen in patients.

Classically, young male patients are affected, and patients typically present with subacute vision loss, caused by a degeneration of retinal ganglion cells and consequent optic nerve degeneration.

Find this Leber Hereditary Optic Neuropathy mnemonic and more mnemonics for Genetic Disorders among Pixorize's visual mnemonics for the USMLE Step 1 and NBME Shelf Exams.