Catechol-O-methyltransferase Val158Met polymorphism and risk of autism spectrum disorders.

OBJECTIVE

Autism spectrum disorders (ASD) are a family of childhood-onset neurodevelopmental disorders with complex genetic mechanisms underlying their aetiology. The aim of this case-control study was to evaluate the effect of the catechol-O-methyltransferase (COMT) gene Val158Met polymorphism on ASD risk in a Chinese Han population.

METHODS

The COMT gene Val158Met polymorphism was detected by polymerase chain reaction-restriction fragment length polymorphism in children (≤ 18 years old) with ASD and healthy control subjects.

RESULTS

The frequency of the Val158/Val158 genotype in children with ASD (22/186; 11.8%) was significantly lower than in controls (38/186; 20.4%). When stratifying by select-item scores on the Autism Diagnostic Interview-Revised protocol, it was found that children with 'current overactivity' and 'ever overactivity' had a significantly lower frequency of the Val158/Val158 genotype than those without. There were no significant associations between the COMT gene Val158Met polymorphism and ASD subtypes.

CONCLUSIONS

The COMT gene Val158Met polymorphism may be a biomarker for phenotypic variation in ASD, but these preliminary findings remain tentative, pending replication in larger, independent samples.