BATTEN disease is the name for a collection of rare, inherited, fatal conditions that often begin in childhood. One form, called CLN3 disease, is characterized by progressive loss of vision at 4–7 years of age, followed by learning and behavior problems, cognitive decline, and seizures.
The genetic changes underlying different types of Batten disease are well established, but how they cause disease is less well understood.
A new study reveals how the genetic mutation responsible for CLN3 disease can lead to damages of the photoreceptors in the retina.
In Batten disease, which involves progressive degeneration of the nervous system and usually starts in childhood, gene mutations cause interferences with the ability of cells to recycle their waste.
Batten disease is not a single condition but a collection of rare, fatal disorders that are formally known as neuronal ceroid lipofuscinoses. They share some features but differ in terms of severity and the age at which symptoms first appear.
The “juvenile-onset” form of the disease, called CLN3 disease, involves vision loss at 4–7 years of age, followed by worsening learning and behavioral problems, dementia, and seizures by around 10 years.
Teenagers with CLN3 disease develop problems with movement and language. Most of those with the condition die between the ages of 15 and 30.
CLN3 is a protein in the membranes that surround the various compartments inside cells. Researchers are unsure exactly what the protein typically does, but it appears to be involved in molecular recycling and waste disposal.
In a person with CLN3 disease, a faulty version of the protein damages the light-sensing cells of the retina, eventually leading to blindness.
However, the initial cause has been unclear from postmortem studies because the damage is so extensive by the time patients have died.
“It is important to understand how vision loss is triggered in this disease, what is primary and what is secondary, and this will allow us to develop new therapeutic strategies,” says Ruchira Singh, Ph.D., an associate professor in the Department of Ophthalmology and Center for Visual Science at the university and senior author of the study. The research has been published in the journal Communications Biology.
