Best disease – draft

Unlike some eye conditions that are linked to lifestyle or environmental factors, Best disease is primarily a genetic condition passed down through families. Several factors are associated with the development of Best disease:

• Genetics: Best disease is usually caused by mutations in the BEST1 gene, which provides instructions for making a protein that helps retinal cells function properly.
• Inheritance: The condition is typically inherited in an autosomal dominant pattern³, meaning a child only needs to inherit one altered copy of the gene from a parent to develop the disease.
• Family history: Because Best disease is inherited, people with a family history of the condition are more likely to develop it.
• Retinal cell dysfunction: Mutations in the BEST1 gene affect the retinal pigment epithelium (RPE), a layer of cells that supports the light-sensing cells of the retina.
• Age of onset: Best disease often develops during childhood or adolescence, although symptoms may not become visible until later on.

Best disease will often develops gradually and might not bring any noticeable symptoms in its early stages. Changes in vision may become more apparent over time, which is why regular eye examinations are important for early detection and monitoring.

Symptoms of Best disease are different for everyone, but make an appointment with your optician if you notice any of the following:

• Blurred or reduced central vision.
• Difficulty reading or recognising faces.
• Distorted vision, where straight lines may appear wavy (metamorphopsia⁴).
• A yellowish spot or lesion in the central retina (macula), often detected during an eye exam.
• Gradual loss of visual clarity over time.
• Sensitivity to light in some cases.

If symptoms progress or suddenly get worse, it’s important to seek professional advice as soon as you can to protect your vision.

Best disease is most commonly diagnosed through a comprehensive eye examination. Regular eye tests are key, especially if you have a family history of the condition, as early changes can be detected before noticeable vision loss occurs.

During your appointment, your eye care professional (optometrist or ophthalmologist) will carry out a series of tests to assess the health of your retina and macula.

If your examiner suspects Best disease, they may refer you to a retinal specialist for further evaluation and confirmation of the diagnosis.

Common tests used to diagnose Best disease include, Optical Coherence Tomography (OCT) to capture detailed cross-sectional images of the retina and Fundus Photography to document the appearance of the macula.

Current treatments:

Although there is currently no cure for Best disease, there are treatments available to help manage symptoms and slow down the progress of vision changes. The kind of treatment varies depending on the stage of the condition and the specific complications that may arise.

Treatments may include:

• frequent monitoring by an eye specialist to monitor any significant changes
• medications or injections if abnormal blood vessels develop
• lifestyle changes to support overall eye health

In many cases, Best disease evolves slowly, and many people maintain healthy vision for years. Support is available including guidance on living with sight loss.

Potential treatments:

At Sight Research UK, we are working tirelessly to find solutions to treat Best disease. Your eye specialist can let you know if there are any clinical trials you could participate in or you can find an active clinical trial here. Here are just a few of our projects that we’ve been working on with researchers all over the UK: