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Dopamine Beta-Hydroxylase Deficiency: DBH Sequencing

Alternate test name

Norepinephrine Deficiency; Noradrenaline Deficiency

Gene name / Alternate gene name
  • DBH
  • DBM
Dopamine beta-hydroxylase (Dopamine beta-monooxygenase)
Lab area
Genome Diagnostics - Molecular Genetics
Method and equipment
Expected turn-around time
STAT: 2-3 weeks Routine: 4-6 weeks
Specimen type

Blood; gDNA.

For details about specimen requirements, please refer to: Specimen Type & Requirements (PDF).

Specimen requirements
  • Blood: 5-10 mL in EDTA, 0.5 mL in EDTA (neonate); 
  • DNA-minimum 10 ug in 100 uL low TE (pH8.0)
Storage and transportation

Room Temperature

For details about specimen requirements, please refer to: Specimen Type and Requirements

Special requirements

Special Instructions for Genome Diagnostics Samples

If sample shipment >48 hours, ship on ice.

Shipping information
The Hospital for Sick Children
Division of Genome Diagnostics
555 University Avenue, Black Wing, Room 3416
Toronto, ON
M5G 1X8
Phone: 416-813-7200 ext. 2
Hours: Monday to Friday, 8 a.m. to 4:30 p.m.
Off hours: Please send to Rapid Response Laboratory, 555 University Avenue, Room 3642
Email Molecular Lab:
Email Cytogenetics:
Background and clinical significance

Dopamine beta-Hydroxylase deficiency (DBHD) is a rare autosomal recessive form of primary autonomic failure characterized by a complete absence of noradrenaline and adrenaline in plasma together with increased dopamine plasma levels. DBH deficiency is mainly characterized by impaired exercise intolerance, severe orthostatic hypotension and persistent ptosis. These findings generally worsen in late adolescence and early adulthood.

DBHD is caused by a mutation in the DBH gene, located on chromosome 9 (9q34). Dopamine beta-hydroxylase is a copper-containg enzyme important in the synthesis of catecholamines, namely the conversion of dopamine to norepinephrine. Biochemical findings in individuals with DBHD include complete absence of plasma norepinephrine and epinephrine in conjunction with elevated plasma dopamine levels.

DBHD occurs when an individual receives two copies of a defective gene, one from each parent. Any person with one copy of the defective DBH gene is a carrier. Carriers do not have DBHD and will not develop the disease. However, if their partner is also a carrier, there is a one in four chance (25%) that their baby will be born with DBHD. There is a three in four chance (75%) that their baby will not have DBHD.

See related information sheet: Dopamine Beta Hydroxylase Deficiency

Disease condition

Dopamine Beta-Hydroxylase Deficiency

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