Monoamine oxidase A deficiency

Alternate names

Brunner syndrome

Definition

Monoamine oxidase A deficiency is a rare condition that is characterized by mild intellectual disability and behavioral difficulties (including aggressive and sometimes violent behaviors and autistic features).

Epidemiology

Monoamine oxidase A deficiency is very rare condition. Its prevalence is unknown.

Cause

• Monoamine oxidase A deficiency is caused by changes (mutations) in the MAOA gene.
• This gene provides instructions for making an enzyme called monoamine oxidase A.

Gene mutations

Mutations in the MAOA gene reduce monoamine oxidase A activity, which causes serotonin and other neurotransmitters to build up in the brain.

Inheritance

X-linked recessive inheritance

This condition is inherited in an X-linked recessive manner.

Onset

Signs and symptoms generally develop in childhood and the condition is seen almost exclusively in males.

Signs and symptoms

• Affected people may also experience night terrors, tremor, stereotypical hand movements, and/or occasional body twitches.
• Most boys with monoamine oxidase A deficiency are less able to control their impulses than their peers, causing aggressive or violent outbursts.
• In addition, affected individuals may have features of other behavioral disorders, including autism spectrum disorder and attention-deficit/hyperactivity disorder (ADHD).
• These features can include obsessive behaviors, difficulty forming friendships, and problems focusing attention.
• Sleep problems, such as trouble falling asleep or night terrors, can also occur in monoamine oxidase A deficiency.
• Some people with monoamine oxidase A deficiency have episodes of skin flushing, sweating, headaches, or diarrhea.
• Similar episodes can occur in female family members of males with monoamine oxidase A deficiency, although females do not experience other signs or symptoms of the condition.

Clinical presentation

For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed.

80%-99% of people have these symptoms

• Behavioral abnormality(Behavioral changes)
• Cognitive impairment(Abnormality of cognition)

5%-29% of people have these symptoms

• Motor delay

1%-4% of people have these symptoms

• Diarrhea(Watery stool)
• Flushing

Diagnosis

• Brunner syndrome is diagnosed by genetic testing for specific mutations of the MAOA gene.
• Since the syndrome is so rare, it's usually only suspected and tested for if there are other diagnosed instances of the syndrome in one's direct family.

Treatment

• Treatment is based on the signs and symptoms present in each person.
• Some recent studies suggest that cautious treatment with certain medications (called selective serotonin reuptake inhibitors) and dietary modifications can improve symptoms.

NIH genetic and rare disease info

• NIH info on Monoamine oxidase A deficiency

Monoamine oxidase A deficiency is a rare disease.

Monoamine oxidase A deficiency Resources
Most recent articles Ongoing trials	Wikipedia