The functional association between COMT gene polymorphism and visual attention in schizophrenic psychosis

Abstract

Catechol-O-methyl transferase (COMT) is the postsynaptic enzyme that inactivates released dopamine and other catacholamins. The COMT activity is polymorphic due to the G to A transition at codon 158 on chromosome 22q11 which translates into valine-to-methionine change in the peptide sequence.

COMT with Val allele more rapidly inactivate released dopamine comparing to Met allele. In our study we found in the group of 44 patients with schizophrenic disorder that COMT polymorphism influences the outcome in visual attention measured by the CPT II test.

ValVal homozygotes have worst outcome in commission errors and reaction time (p 0,05). These finding confirms the role of COMT polymorphism and in cognitive deficit in schizophrenia.