Catechol-O-methyltransferase Val158Met polymorphism is associated with methylphenidate response in ADHD children
Eva Kereszturi1, Zsanett Tarnok, Emese Bognar
1Institute of Medical Chemistry, Molecular Biology and Pathobiochemistry, Semmelweis University, Budapest, Hungary.
Summary
The Val-allele of the COMT Val158Met polymorphism is associated with attention deficit hyperactivity disorder (ADHD) and predicts a better response to methylphenidate treatment in children with ADHD.
Area of Science:
- Pharmacogenetics
- Neuroscience
- Genetics
Background:
- Methylphenidate is a common ADHD treatment, but not universally effective.
- Identifying genetic markers for methylphenidate response is crucial.
- Dopaminergic polymorphisms have been implicated in ADHD and drug response.
Purpose of the Study:
- To investigate the role of three dopaminergic polymorphisms in ADHD.
- To identify genetic markers predicting methylphenidate response in ADHD patients.
Main Methods:
- Case-control study and pharmacogenetic association analyses in an ADHD population.
- Investigated dopamine D4 receptor (DRD4) and dopamine transporter (DAT1) VNTRs.
- Analyzed the COMT Val158Met polymorphism in relation to ADHD and methylphenidate response.
Main Results:
- DRD4 and DAT1 VNTRs showed no substantial involvement in ADHD.
- The high-activity Val-allele of COMT Val158Met was more frequent in ADHD cases.
- COMT Val-allele and Val/Val genotype were associated with good methylphenidate response.
- Significant interaction between COMT genotype and methylphenidate response on hyperactivity-impulsivity symptoms.
Conclusions:
- COMT Val158Met polymorphism, particularly the Val-allele, is a significant genetic marker for ADHD.
- This polymorphism predicts methylphenidate treatment response in ADHD.
- COMT genotype may influence methylphenidate efficacy through prefrontal dopamine regulation.
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