Association between Intelligence and COMT Genotypes in Chinese Healthy Children

Catechol-O-methyl transferase (COMT) influences dopamine concentration in the pre-frontal cortex (PFC). The G/A transition in the exon 4 of the COMT gene, which results in a valine (Val) to methionine (Met) amino acid substitution (Val158Met), can bring on different enzymatic activities. Much research has found that the Met/Met genotype associated with low enzymatic activity and may enhance cognitive function. We applied one-way ANOVA to detect the effect of the COMT genotypes to intelligence in 108 Chinese children with polymerase chain reaction (PCR) methods. We found COMT Val158Met polymorphism had a significant main effect on intelligence (F (2, 102) = 3.47, p=0.035) and it could predict 4.7% of intelligence. Our results also suggest that Met/Met genotype has a positive effect on intelligence. However, we found no significant interaction between gender and COMT genotype to intelligence.