Test Code: 4608

Brunner Syndrome: MAOA Gene Deletion/Duplication
Test Code: 4608
Turnaround time: 3 weeks

CONDITION DESCRIPTION

Mutations in the MAOA gene result in the X-linked disorder Brunner syndrome, or monoamine oxidase deficiency, which is characterized in part by severe impulsive behavior and mild nondysmorphic intellectual disability. MAOA encodes for monoamine oxidase A, an enzyme that degrades amine neurotransmitters such as dopamine, norepinephrine, and serotonin.

For patients with suspected Brunner syndrome, sequence analysis is recommended as the first step in mutation identification. For patients in whom mutations are not identified by full gene sequencing, deletion/duplication analysis is appropriate.

References:
• OMIM 309850: Monoamine Oxidase A; MAOA
• OMIM 300615: Brunner Syndrome
• Gunter et al. Behavioral Genetics in Antisocial Spectrum Disorders and Psychopathy: A Review of the Recent Literature. (2010). Behav. Sci. Law 28: 148-173.

GENES
MAOA

INDICATIONS
This test is indicated for:

  • Confirmation of a clinical diagnosis of Brunner syndrome in an individual in whom sequence analysis was negative.
  • Carrier testing in adults with a family history of Brunner syndrome in whom sequence analysis was negative.

METHODOLOGY

DNA isolated from peripheral blood is hybridized to a CGH array to detect deletions and duplications. The targeted CGH array has overlapping probes which cover the entire genomic region.

Please note that a “backbone” of probes across the entire genome are included on the array for analytical and quality control purposes. Rarely, off- target copy number variants causative of disease may be identified that may or may not be related to the patient’s phenotype. Only known pathogenic off-target copy number variants will be reported. Off-target copy number variants of unknown clinical significance will not be reported.

DETECTION

Detection is limited to duplications and deletions. The CGH array will not detect point or intronic mutations. Results of molecular analysis must be interpreted in the context of the patient’s clinical and/or biochemical phenotype.

SPECIMEN REQUIREMENTS

Submit only 1 of the following specimen types
* Preferred specimen type: Whole Blood

Type: Whole Blood
Specimen Requirements:
In EDTA (purple top) or ACD (yellow top) tube: Infants (2 years): 3-5 ml
Older Children & Adults: 5-10 ml

Specimen Collection and Shipping: Refrigerate until time of shipment. Ship sample within 5 days of collection at room temperature with overnight delivery.

Type: Saliva
Specimen Requirements:
OrageneTM Saliva Collection kit (available through CEN4GEN) used according to manufacturer instructions.

Specimen Collection and Shipping: Store sample at room temperature. Ship sample within 5 days of collection at room temperature with overnight delivery.

SPECIAL INSTRUCTIONS
Submit copies of diagnostic biochemical test results with the sample, if appropriate.
Sequence analysis is required before deletion/duplication analysis by targeted CGH array. If sequencing is performed by another third party provider, please submit a copy of the sequencing report with the test requisition.

RELATED TESTS

  • Sequence analysis of the MAOA gene is available and is required before deletion/duplication analysis.
  • Custom diagnostic mutation analysis (test code: 6875) is available to family members if mutations are identified by targeted mutation testing or sequencing analysis.