Key result
Adults with 22q11.2 deletion syndrome demonstrated significantly lower dopamine D2/3 receptor binding potential in the anterior cingulate gyrus compared to healthy controls.
Why the study?
Extracellular dopamine levels may be increased in prefrontal brain areas in 22q11.2 deletion syndrome, motivating examination of dopamine D2/3 receptor binding as a proxy of frontal dopamine levels.
Does 22q11.2 deletion syndrome alter frontal dopamine D2/3 receptor binding potential compared to healthy controls?
Case-Control (n=30)
Yes
Does 22q11.2 deletion syndrome alter frontal dopamine D2/3 receptor binding potential compared to healthy controls?
Absolute Event Rate: 0.35% vs 0.49%
p-value: p=0.002
Adults with 22q11.2 deletion syndrome exhibit lower frontal dopamine D2/3 receptor binding, suggesting a hyperdopaminergic state that may contribute to their increased risk for cognitive impairments and psychosis.
May link 22q11.2DS to psychosis risk via dopamine dysregulation; hypothesis-generating without practice implications.
BACKGROUND: The 22q11.2 deletion syndrome (22q11DS) is caused by a deletion on chromosome 22 locus q11.2. This copy number variant results in haplo-insufficiency of the catechol-O-methyltransferase (COMT) gene, and is associated with a significant increase in the risk for developing cognitive impairments and psychosis. The COMT gene encodes an enzyme that primarily modulates clearance of dopamine (DA) from the synaptic cleft, especially in the prefrontal cortical areas. Consequently, extracellular DA levels may be increased in prefrontal brain areas in 22q11DS, which may underlie the well-documented susceptibility for cognitive impairments and psychosis in affected individuals. This study aims to examine DA D2/3 receptor binding in frontal brain regions in adults with 22q11DS, as a proxy of frontal DA levels. METHODS: The study was performed in 14 non-psychotic, relatively high functioning adults with 22q11DS and 16 age- and gender-matched healthy controls (HCs), who underwent DA D2/3 receptor [18F]fallypride PET imaging. Frontal binding potential (BPND) was used as the main outcome measure. RESULTS: BPND was significantly lower in adults with 22q11DS compared with HCs in the prefrontal cortex and the anterior cingulate gyrus. After Bonferroni correction significance remained for the anterior cingulate gyrus. There were no between-group differences in BPND in the orbitofrontal cortex and anterior cingulate cortex. CONCLUSIONS: This study is the first to demonstrate lower frontal D2/3 receptor binding in adults with 22q11DS. It suggests that a 22q11.2 deletion affects frontal dopaminergic neurotransmission.
No takes yet. Share an insight, caveat, or question.
Duin et al. (2019) conducted a case-control in 22q11.2 deletion syndrome (n=30). 22q11.2 deletion syndrome vs. Healthy controls was evaluated on Dopamine D2/3 receptor binding potential (BPND) in the anterior cingulate gyrus (p=0.002). Adults with 22q11.2 deletion syndrome demonstrated significantly lower dopamine D2/3 receptor binding potential in the anterior cingulate gyrus compared to healthy controls.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: