SNP Shot: Genomic Insights

Dopamine beta (β)-hydroxylase deficiency impacts the autonomic nervous system, which manages automatic bodily functions like blood pressure and temperature control. This condition can manifest as early as infancy. Initial signs may involve vomiting spells, dehydration, low blood pressure (hypotension), trouble regulating body temperature, and low blood sugar (hypoglycemia).

A hallmark of dopamine β-hydroxylase deficiency is a significant decrease in blood pressure when standing up (orthostatic hypotension). This can lead to lightheadedness, blurry vision, or fainting. This blood pressure drop is often worse when rising in the morning, in hot weather, and with advancing age. Because they struggle to maintain normal blood pressure, individuals with this deficiency often experience extreme tiredness during physical activity (exercise intolerance).

Additional characteristics of dopamine β-hydroxylase deficiency can include drooping eyelids (ptosis), a stuffy nose, and difficulty standing for extended periods. Males with the condition may also experience retrograde ejaculation, where semen is released into the bladder instead of being expelled. Less frequent signs involve unusually flexible joints (hypermobility) and muscle weakness.

Inheritance:

Dopamine β-hydroxylase deficiency follows an autosomal recessive inheritance pattern. This means that both copies of the affected gene within a person's cells must have mutations for the condition to develop. Individuals inheriting only one copy of the mutated gene from each parent typically do not exhibit symptoms of the condition but are carriers.