Definition of Neuronal ceroid lipofuscinoses (NCLS):

Neuronal ceroid lipofuscinoses (NCLS) refers to a group of rare, inherited disorders of the nerve cells.

There are three main types of NCLS:

• Adult (Kufs' or Parry's disease)
• Juvenile (Batten disease)
• Late infantile (Jansky-Bielschowsky)

Causes, incidence, and risk factors:

NCLS is a type of neurodegenerative disorder. It involves a build-up of an abnormal material called lipofuscin in the brain. Evidence suggests that NCLS is caused by problems with the brain's ability to remove and recycle proteins.

The disorder may be seen at birth, but it is usually diagnosed much later. Children develop lack of muscle coordination (ataxia), walking problems, sight problems, retardation, and seizures. The younger the person is when the disease appears, the greater the risk for disability and early death.

Lipofuscinoses are inherited as autosomal recessive traits. That means if both parents carry the trait, each child has:

• A 1 in 4 chance of having the disease
• A 2 in 4 chance of not having the disease but carrying the trait
• A 1 in 4 chance of not having the disease and not being a carrier