Leber's Hereditary Optic Neuropathy

Leber's Hereditary Optic Neuropathy is a rare maternaly inheredited eye condition that affects men more than women at a rate of 90% to 10%.

LHON was first discovered by Theodore Leber in the 19th century, but we didn't really start to understand how it was inherited until the late 1980's. Leber's usually affects one eye first and central vision is lost in that eye over a period of a few weeks. A month or two later, the second eye is affected in the same way. After a few weeks the eyesight stops getting worse.

This is the most common pattern of development, but LHON can affect someone very suddenly, or can affect them more gradually over a period of years. Not everyone in a family affected by Leber's will lose their eyesight, and we can't tell yet know who will get symptoms and who won't. We do know that Leber's is inherited through a gene which is passed on only through the egg cell from the mother. Men can't pass on Leber's Hereditary Optic Neuropathy to their children.

Scientists believe that the particdular gene changes linked to Leber's Hereditary Optic Neuropathy lower the amount of energy available to the cells of the optic nerve and retina. These cells are damaged and can even die because of this lack of energy. The damage to the optic nerve and retina is what causes the symptoms of Leber's.

Doreid Berro has written an informative paper about LHON and it's published on the internet with documentation.

Genetics Home Reference also has quite a bit of information about Leber's on their site.

Carver Laboratory has information about Leber's and other hereditary eye conditions. They also have some interesting pictures on their website.

I never knew there were so many different causes of low vision.

Dale L. Edwards