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Metachromatic leukodystrophy

Other Names for this Disease
  • ARSA deficiency
  • Arylsulfatase A deficiency
  • Cerebral sclerosis diffuse metachromatic form
  • Cerebroside sulfatase deficiency
  • Leukodystrophy metachromatic
More Names
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What is metachromatic leukodystrophy?

How is metachromatic leukodystrophy inherited?

What is metachromatic leukodystrophy?

Metachromatic leukodystrophy is an inherited condition characterized by the accumulation of fats called sulfatides in cells, especially cells of the nervous system. This accumulation results in progressive destruction of white matter of the brain, which consists of nerve fibers covered by myelin. Affected individuals experience progressive deterioration of intellectual functions and motor skills, such as the ability to walk. They also develop loss of sensation in the extremities, incontinence, seizures, paralysis, inability to speak, blindness, and hearing loss. Eventually they lose awareness of their surroundings and become unresponsive. This condition is inherited in an autosomal recessive pattern and is caused by mutations in the ARSA and PSAP genes.[1]

Last updated: 5/19/2011

How is metachromatic leukodystrophy inherited?

Metachromatic leukodystrophy is inherited in an autosomal recessive manner. This means that both copies of the disease-causing gene in each cell must have a mutation for an individual to be affected. Individuals inherit two copies of each gene - one copy from each parent. Typically, an individual is affected because they inherited a mutated copy of the gene from each parent. Individuals with one mutated copy of the gene (such as an unaffected parent of an affected individual) are referred to as carriers; carriers typically do not have any signs or symptoms of the condition.

When two carriers of an autosomal recessive condition have children, each child has a 25% (1 in 4) chance to have the condition, a 50% (1 in 2) chance to be a carrier like each of the parents, and a 25% chance to not have the condition and not be a carrier.
Last updated: 6/28/2012

  1. Metachromatic leukodystrophy. Genetics Home Reference. September 2007; Accessed 5/19/2011.