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Melatonin Levels in 89 Individuals With Smith Magenis Syndrome.
1Governor Kremers Centre, Maastricht University, Maastricht, the Netherlands.
American Journal of Medical Genetics. Part A
|May 18, 2026
Summary
Melatonin (MT) treatment for Smith-Magenis syndrome (SMS) can cause high daytime MT levels. Monitoring MT levels and considering individual metabolism is crucial for effective sleep disorder management in SMS patients.
Area of Science:
- Biochemistry
- Genetics
- Sleep Medicine
Background:
- Smith-Magenis syndrome (SMS) is associated with circadian rhythm disruption.
- Melatonin (MT) is commonly used to manage sleep disturbances in SMS.
- Standard MT treatment can lead to elevated daytime MT levels, exacerbating sleep disorders.
Purpose of the Study:
- To retrospectively evaluate melatonin (MT) levels in Smith-Magenis syndrome (SMS) patients.
- To investigate the relationship between exogenous MT use and MT levels in SMS.
- To assess the utility of CYP1A2 genotyping in predicting MT metabolism.
Main Methods:
- Retrospective analysis of MT data from 89 SMS patients.
- Comparison of MT levels between patients using and not using exogenous MT.
- Analysis of MT level changes after MT discontinuation and initiation.
- CYP1A2 genotyping in five patients with high MT levels during MT use.
Main Results:
- Patients on exogenous MT had significantly higher mean MT levels (p < 0.0001).
- Discontinuation of exogenous MT led to significant MT level reduction in 9 participants (p = 0.0037).
- MT levels increased significantly after MT therapy initiation in 12 participants (p = 0.028).
- CYP1A2 genotyping (CYP1A2*1F) in five patients did not correlate with high MT levels, suggesting it's unsuitable for estimating enzyme activity.
Conclusions:
- Exogenous melatonin (MT) administration significantly increases MT levels in Smith-Magenis syndrome (SMS) patients.
- CYP1A2 genotyping is not a reliable indicator of MT metabolism in SMS.
- Measuring MT levels before and during treatment is recommended for optimal dosing and management of sleep disturbances in SMS.
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