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Eye and hearing diseases

Leber hereditary optic neuropathy (LHON)

An inherited disease that affects the optic nerve. It usually causes painless loss of central vision at a young age. It is much more common in men.

Not part of the panel of Türkiye's National Newborn Screening Programme (heel-prick test). Source

Prepare an emergency card

This page is translated from the Turkish original.

This disease is followed through the “Eye and hearing diseases” group.

Understanding the disease

This section has not yet been reviewed by a physician. It summarises patient information from sources such as MedlinePlus, Orphanet and the NHS in plain language. The disease can differ from person to person; talk to your doctor about diagnosis and treatment.

What happens in this disease?

The disease is caused by a change in the genes of the mitochondria, which produce energy in the cell. The cells of the optic nerve, which carries visual information to the brain, are damaged. First one eye is affected, then the other eye within weeks or months. Central vision is affected the most.

Which symptoms can occur?

Symptoms usually begin between the ages of 10 and the late 20s. Some people who carry the gene change never have any symptoms.

  • Painless blurred and hazy vision
  • Vision loss first in one eye, then in the other
  • Loss of central vision; reading and recognizing faces become difficult
  • Reduced color vision
  • Some spontaneous improvement in central vision (in a small number of people)
  • In some families, tremor, movement disorders or heart rhythm problems (rare)

How is it diagnosed?

The eye doctor widens the pupil and looks at the head of the optic nerve. The optic nerve is examined with a visual field test and OCT. The diagnosis is confirmed by checking the mitochondrial genes in the blood. Three common gene changes explain most cases.

Treatment and care

In Europe, there is an approved drug treatment specific to the disease for vision loss in patients aged 12 and over. Aids for people with low vision and job support are also important. Avoiding smoking and too much alcohol is recommended. New methods such as gene therapy are being studied. The doctor who follows the disease decides which treatment is suitable.

For the family: inheritance and genetic counselling

LHON is passed on only from the mother. Mitochondria are passed to the child only through the egg cell. All children of a mother who carries the gene change receive this change. It is not passed from father to child. Most carriers never have any vision loss; in women this chance is even lower. Genetic counselling helps to understand who in the family is at risk.

Source: MedlinePlus Genetics: Leber hereditary optic neuropathy · NORD: Leber Hereditary Optic Neuropathy · EMA: Raxone (LHON) EPAR

Key facts

How common is it?
Prevalence: 1-9 per 100 000 (Worldwide)
How is it inherited?
Mitochondrial inheritance
When does it usually start?
Adolescence, Adulthood
Gene(s) involved
MT-ATP6, MT-CO3, MT-CYB, MT-ND1, MT-ND2, MT-ND4

These facts are taken from Orphanet and MedlinePlus records (last checked: October 7, 2026). Frequency values are approximate ranges.

You are not alone: patient associations in Türkiye

Non-profit patient and family organizations in Türkiye working on this disease or disease group. Links are for information; Doktorclub is not affiliated with these organizations and does not endorse them.

We could not find a patient association specific to this disease.

For all rare diseases: Nadir Hastalıklar Federasyonu

Support and help

Doktorclub does not diagnose, recommend treatments or refer you to hospitals or doctors. These pages are meant to help you talk with your doctor.

News about LHON

Clinical trials (ClinicalTrials.gov)

A clinical trial is a regulated study that tests whether a new treatment is safe and whether it works, in patients who volunteer. Most trials look for a certain age, genetic change and health condition. Taking part is voluntary.

This list is not a treatment recommendation. Treatments tested in phase 1–3 trials are investigational (experimental): their efficacy and safety have not yet been proven and they are not approved treatments. Taking part depends on each trial’s criteria and a physician’s assessment; the first step is to talk to the doctor who manages your care.

Questions you can ask your doctor

  • Could this trial be suitable for us?
  • If we take part, how would current treatment and check-ups be affected?
  • Where does the trial take place, and how are travel and accommodation handled?
  • What happens if we want to leave the trial?

ClinicalTrials.gov lists 7 active interventional studies for this disease. 4 are recruiting now; none has a site in Türkiye. Last checked: October 7, 2026.

Selected records (studies with a site in Türkiye first):

See all studies on ClinicalTrials.gov · Joining clinical trials

Eye and hearing diseases: other news

Medical codes (for talking with your doctor and finding sources)

These codes identify the disease in international classifications and databases. They can help when you talk with your doctor or look for reliable sources.

Orphanet code: ORPHA:104

No separate ICD-11 code; WHO classifies this disease under: 8C73.Y

Codes checked against WHO ICD-11 and Orphanet on October 7, 2026.

This page provides general information and does not replace diagnosis or treatment. Talk to your doctor about symptoms, diagnosis and treatment.

The information on these pages is for general information only and does not replace medical advice. Talk to your doctor about diagnosis and treatment decisions. In an emergency in Türkiye, call 112.

Every update is based on an open source and labeled with its level of evidence. No advertising and no drug brand names. Our scientific principles

This page was translated from Turkish by the Doktorclub editorial team.