Definition:
Early juvenile CLN6 disease is part of a group of progressive degenerative neurometabolic disorders known as neuronal ceroid lipofuscinoses (NCLs). NCLs are characterized by an abnormal accumulation of lipopigaments, subtances combined of fats and proteins within the brain’s nerve cells, eyes, skin, muscle, and within other tissues throughout the body.

Although this disorder has clinical symptoms similar to other NCLs, it is distinct because its cause is known. The cause of a number of NCLs still remains nebulous. Early juvenile CLN6 disorder is caused by a mutation on the CLN6 gene which leads to an accumulation of transmembrane proteins in the cells. The gene CLN6 provides the code for a protein known as linclin, which plays an important role in the function of cellular membranes and in providing energy to nerve cells. This mutation essentially eliminates the function of the CLN6 gene and gives rise to the symptoms of this disorder. More than 18 mutations on the CLN6 gene have been identified. This disorder causes nerve cells, found in the brain, retina, and in the central nervous system, to die.

Early juvenile CLN6 predominately affects those of Portuguese, Indian, Pakistani, or Czech origin, although the exact prevalence figures are not known. It is estimated that the NCLs affect two to four of every 100,000 live births in the United States.

Symptoms:
Symptoms of Early juvenile CLN6 begin to be present between ages four and eight, and include blindness, seizures, and loss of cognitive skills. A loss of motor skills typically occurs between four and 10 years of age. As this disorder progresses, the affected individual becomes increasingly incapacitated.

Inheritance Pattern:
Early juvenile CLN6 is an autosomal recessive disorder.

Life Expectancy:
Life Expectancy for Early juvenile CLN6 is between 10 and 30 years of age.

Diagnosis and Testing:
A DNA analysis confirming a mutation on the CLN6 gene is utilized to diagnose Early juvenile CLN6. For this test, blood or a tissue sample is examined from individuals who are suspected of having the disorder or from family members wherein a carrier of the CLN6 gene has been identified. Prenatal screening is also available.

Treatment:
There is no cure for Early juvenile CLN6. Treatment is limited to reducing or controlling the symptoms of this disorder by consulting regularly with neurologists, ophthalmologists and genetic. Neurologists can help to control seizures or nervous system complications. An ophthalmologist monitor vision loss, and physical and occupational therapists assist the affected individual to maintain muscle movement and reduce muscle discomfort.