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Genetic and Rare Diseases Information Center (GARD)

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Adenylosuccinase deficiency

Other Names for this Disease
  • Adenylosuccinate lyase deficiency
  • ADSL deficiency
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What is adenylosuccinase deficiency?

What are the signs and symptoms of adenylosuccinase deficiency?

What is adenylosuccinase deficiency?

Adenylosuccinase deficiency is a rare, inherited metabolic condition that results from a lack of the enzyme adenylosuccinate lyase. Signs and symptoms vary greatly from person to person. In general, affected individuals may have a mix of neurological symptoms, which usually includes abnormalities with cognition and movement, autistic features, epilepsy, muscle wasting, and feeding problems. Although less common, abnormal physical features can include severe growth failure, small head, abnormally shaped head, strabismus, small nose with upturned nostrils, thin upper lip, and low set ears. Adenylosuccinase deficiency is caused by mutations in the ADSL gene and is inherited in an autosomal recessive fashion.[1]
Last updated: 9/8/2011

What are the signs and symptoms of adenylosuccinase deficiency?

The signs and symptoms of adenylosuccinase deficiency vary greatly from person to person. Seizures are observed in 60 percent of affected individuals. Seizures may begin within the first month of life and, in many cases, are the first sign of the condition. Some of the neurological symptoms include floppiness (hypotonia) with severe tension of the hands and feet (hypertonia); muscle wasting; muscle twitchings of the tongue or hands and feet; and crossed eyes (strabismus). Almost all affected individuals experience delayed motor milestones ranging from mild to severe. In the first years of life, growth delay has been observed in 30 percent of affected individuals, mainly related to feeding problems.[1]

Autism has been found to be present in one-third of cases. Some children display unusual behavior such as stereotyped behavior, (hand washing movements, repetitive manipulation of toys, grimacing, clapping hands, rubbing feet, and inappropriate laughter), aggressive behavior, temper tantrums, impulsivity, hyperactivity, short attention span, and hypersensitivity to noise and lights. Many patients show severe intellectual disability, and language delay.[1]
Last updated: 9/8/2011

  1. Adenylosuccinate lyase deficiency. National Organization for Rare Disorders (NORD). 2010; Accessed 9/8/2011.