Varijante gena za katehol-O-metiltransferazu u bolesnika s depresijom

Depresija je jedan od najučestalijih psihijatrijskih poremećaja današnjice, a obilježavaju ga sniženo raspoloženje, gubitak interesa i zadovoljstva, osjećaj krivnje i manje vrijednosti, poremećaji apetita i sna, smanjena koncentracija, nedostatak životne energije te povećani suicidalni rizik. Pojavnost ove ozbiljne bolesti vrlo je složena i uključuje brojne rizične gene i okolišne čimbenike, a njezin nastanak pokušavaju objasniti razne teorije. Prema monoaminskoj hipotezi, na kojoj se zasniva aktualna farmakološka terapija, u podlozi depresije nalazi se poremećaj monoaminskih (serotonin, dopamin, noradrenalin) neurotransmitorskih sustava u mozgu. Katehol-O-metiltransferaza (COMT) je enzim koji razgrađuje kateholamine, uključujući neurotransmitore dopamin i noradrenalin, koji igraju važnu ulogu u nastanku depresivnih simptoma. Enzim je kodiran genom COMT koji se kod ljudi nalazi na 22. kromosomu, a sadrži veliki broj polimorfizama koji mogu imati utjecaj na neurotransmisiju i time pridonijeti razvoju depresije. Iako su raznovrsne studije istraživale varijante gena COMT vezano uz neurofiziološke, bihevioralne i kliničke fenotipove depresije, kao i uz odgovor na terapiju antidepresivnim lijekovima, rezultati iz literature često su oprečni. Kako uloga varijanti gena COMT u razvoju depresije nije jasna, cilj istraživanja bio je utvrditi postoji li u osoba oboljelih od depresije povezanost varijanti rs4680 i rs4818 gena COMT s težinom depresivnih simptoma. Rezultati ovog istraživanja pokazali su da nema statistički značajne povezanosti dviju varijanti gena COMT sa simptomima depresije, osim rs4680 varijante s hipohondrijskim simptomima HAMD ljestvice. Depression is one of the most common psychiatric disorders nowadays characterized by reduced mood, loss of interest and satisfaction, guilt and low self-value, appetite and sleep disorders, reduced concentration, lack of life energy and increased suicid risk. The occurence of this serious disease is very complex and it involves many risk genes and environmental factors so various theories try to explain its origin. According to the monoamine hypothesis, on which current pharmacological therapy is based, depression is characterized by the disruption of monoamine (serotonin, dopamine, noradrenaline) neurotransmitter systems of the brain. Catechol-O-methyltransferase (COMT) is an enzyme that degrades catecholamines, including neurotransmitter dopamine and noradrenaline, which play an important role in the occurrence of depression symptoms. The enzyme is encoded by the gene COMT, which is located on the 22nd chromosome in humans and it contains a large number of polymorphisms that may have an effect on neurotransmission and thus contribute to the development of depression. Although various studies have investigated COMT gene variants associated with neurophysiological, behavioral and clinical phenotypes of depression, as well as responding to antidepressant therapy, the literature results are often contradictory. As the role of the COMT gene in the development of depression is not clear, the aim of the study was to determine whether there is any association between the rs4680 and rs4818 COMT genetic polymorphisms with the severity of depression symptoms in depressed patients. The results of this study showed that there was no statistically significant association of the two COMT gene variants with severity of depression symptoms, except rs4680 with hypochondriacal symptoms of HAMD scale.