Análise de variações genômicas em genes da região cromossômica 22q11.2 em pacientes esquizofrênicos do Estado do Pará

Abstract

The COMT Val158Met and ZDHHC8 rs175174 polymorphisms have received increased attention in the molecular study of schizophrenia not only because they are localised to the main susceptibility locus of the disease, 22q11, but also because they are related to the dopaminergic status of the prefrontal cortex and the activity of several neuronal proteins, respectively. To evaluate the influence of the polymorphic genotypes on schizophrenia, we used real-time PCR to genotype 130 patients and 175 controls in a population from the North Region of Brazil. Our results indicated an absence of association between both polymorphisms and the likelihood of schizophrenia in the population studied. However, when categorised by gender, we found a dichotomous association between the Met/Met genotype of the COMT Val158Met polymorphism and susceptibility to schizophrenia, conferring a higher probability of disease in men (OR = 10.76; CI 95% = 2.09–55.34; p = 0.004) than in women (OR = 0.23; CI 95% = 0.07–0.69; p =0.009). Moreover, the variance analysis showed an association of the genotypes Val/Met (COMT Val158Met) and GG (ZDHHC8 rs175174) with higher average age at onset of schizophrenia. Our study supports the hypothesis of a gender-dependent association of the COMT Val158Met polymorphism with schizophrenia, in addition to suggesting an influence of both polymorphisms studied on the age at disease onset.