MAOA
Chr XXLRmonoamine oxidase A
Also known as: BRNRS, MAO-A
This mitochondrial enzyme catalyzes the oxidative deamination of neurotransmitters including serotonin, dopamine, and norepinephrine. Mutations cause Brunner syndrome, an X-linked recessive disorder characterized by intellectual disability and behavioral abnormalities. The gene is highly constrained against loss-of-function variants, indicating that complete loss of enzyme activity has severe consequences.
Definitive — sufficient evidence for diagnostic panels
Population Genetics & Constraint
gnomAD v4 — loss-of-function & missense intolerance
Among the most LoF-intolerant genes (~top 3%)
Moderately missense-constrained (top ~2.5%)
ClinVar Variant Classifications
0 submitted variants in ClinVar
Protein Context — Lollipop Plot
MAOA · protein map & ClinVar variants
Showing all ClinVar variants across the protein. Search a specific variant to highlight its position.
3D Protein StructureAlphaFold
External Resources
Links to major genomics databases and tools
Clinical Trials
Active and recruiting trials from ClinicalTrials.gov
Genetic and Clinical Correlates of Disruptive Behavior Disorder With and Without Callous-Unemotional Traits
ACTIVE NOT RECRUITINGOnline Study of People Who Have Genetic Changes and Features of Autism: Simons Searchlight
RECRUITINGExternal Resources
Links to major genomics databases and tools