New functional single nucleotide polymorphism (Ala72Ser) in the COMT gene is associated with aggressive behavior in male schizophrenia

A new functional single nucleotide polymorphism (SNP) Ala72Ser in the COMT gene was discovered recently. The purpose of our study is to examine the association between Ala72Ser and Val158Met functional polymorphisms in COMT gene and homicidal behavior in schizophrenia. DNA was genotyped for the Ala72Ser and Val158Met SNPs of the COMT gene in a sample of 93 schizophrenic patients who committed homicide (H-SCZ) and 100 schizophrenic patients who had never committed homicide (NH-SCZ). A statistically significant difference was found in genotype distribution and allele frequencies in SNP Ala72Ser of COMT gene between H-SCZ and NH-SCZ group. In haplotype analysis, the frequency of the combination of high-high activity allele (Ala-Val) was lower in H-SCZ group than in NH-SCZ group (P = 0.000069). Our study showed a highly significant association between a COMT haplotype of two functional SNPs and aggressive behavior in schizophrenia.