SNP Shot: Genomic Insights

Dopamine transporter deficiency syndrome is an uncommon movement disorder. It's also called infantile parkinsonism-dystonia because movement problems like dystonia and parkinsonism typically begin in infancy and get worse over time. However, symptoms might not appear until childhood or even later.

Individuals with dopamine transporter deficiency syndrome experience dystonia, which involves involuntary, prolonged muscle contractions. This dystonia is generalized, impacting numerous muscles throughout the body. The persistent muscle cramping and spasms make it challenging to perform everyday tasks such as speaking, eating, drinking, grasping objects, and walking.

As the condition progresses, individuals develop parkinsonism, characterized by movement abnormalities such as tremors, unusually slow movements (bradykinesia), stiffness (rigidity), and difficulty maintaining balance and posture (postural instability). Additional signs and symptoms can include abnormal eye movements, reduced facial expressions (hypomimia), sleep disturbances, recurring pneumonia, and digestive issues like gastroesophageal reflux and constipation.

The lifespan of individuals with dopamine transporter deficiency syndrome may be shorter than average, though the long-term impact of this condition remains unclear. Children with the condition have died due to pneumonia and breathing difficulties. When the initial signs and symptoms manifest later in life, affected individuals may live into adulthood.

Inheritance:

The inheritance pattern of this condition is autosomal recessive. This means that both copies of the responsible gene in each cell must have mutations for the condition to develop. Individuals with an autosomal recessive condition inherit one copy of the mutated gene from each parent, who are typically carriers and do not exhibit signs or symptoms of the condition themselves.