Leber Hereditary Optic Neuropathy: The Genetic Cause of Vision Loss

Leber hereditary optic neuropathy (LHON) is a condition that causes vision loss. In this article you’ll learn more about this hereditary eye condition, what causes vision loss in LHON, symptoms to look out for and the various treatment options available.

What is Leber hereditary optic neuropathy?

Leber hereditary optic neuropathy (LHON) causes issues with central vision. Those with LOHN usually notice a clouding or blurring in their vision at first, the condition then progresses to a loss of sharpness/detail and a loss of colour vision. This can occur in either one or both eyes. For most people with this condition, vision loss is irreversible, but some may recover part of their vision.

As this condition impairs central vision, everyday tasks such as reading, driving and distinguishing people’s faces can become very difficult.

What is Leber hereditary optic neuropathy plus?

Leber hereditary optic neuropathy plus is the same condition that causes severe vision loss, along with some other symptoms that are not eye related. These extra symptoms include:

• Tremors
• Movement disorders
• Cardiac conduction defects
• Multiple sclerosis

What causes Leber hereditary optic neuropathy?

LHON is caused by genetic mutations in mitochondrial DNA. A mitochondrial condition, this means that it can only be inherited from the mother. Only females can give this gene on to offspring, whereas males with the condition cannot.

What are the signs and symptoms of LHON?

As mentioned earlier, the first sign of LHON is usually cloudy or blurry vision. The central vision is the most severely affected, colour perception and the ability to see sharp details will be lost. Most will notice vision loss in one eye, with the second eye following after several months.

Leber hereditary optic neuropathy – inheritance

Those with LHON will not necessarily have a family history of the condition because the carrier of the mutated gene may not experience any symptoms themselves. Women are often carriers of the mutated gene, but they don’t experience symptoms of vision loss themselves, whereas men are 4-5 times more likely to suffer from vision loss. Although women tend not to experience symptoms, they will always pass the condition onto their children.

Diagnosis of Leber hereditary optic neuropathy

Diagnosis is usually achieved through vision tests. This can include observing changes in the optic disc and visual field as well as image testing/optical coherence tomography. Molecular genetic testing can also be done to find out whether someone has the condition.

Treatment options for LHON

LHON treatment options focus on managing the symptoms of vision loss. This can be done through visual aids. There is some research to suggest positive outcomes for those treated with idebenone.

Avoiding alcohol and cigarettes is also advised, as those with LHON have been observed to have more severe symptoms when engaging in drinking and smoking compared with those that don’t. For tips on how to improve your eye health with changes to lifestyle, check out our blog.

Disclaimer: The advice in this article is for informational purposes only and does not replace medical care or an in-person check-up. Please check with an eyecare professional before purchasing any products or remedies. For information on our article review process, please refer to our Editorial Policy.