vol. 3 núm. 1 (2017)

Schizophrenia is a mental disorder based on multiple factors, so the etiology is still under discussion; many candidates have been identified as genetic risk factors to the phenotype, including the postulates in the meta-analysis. APOE gene codes for a protein involved in the transport of lipids being the variable candidate e4 important risk factor for schizophrenia and polymorphism VAL66MET BDNF involved in intercellular secretion alterations in the neurotrophin, postulated in association with the disorder. A systematic review was conducted through various databases, compiling 25 case-control studies related to the association of some of the variables to schizophrenia, under strict eligibility criteria, among them meta-analytic association was determined using the random effects model, for inferring the impact of the risk allele and the genotype at schizophrenia. It was obtained a slight association of the e4 variant in Caucasians. On the other hand neither the Met genotype carrier, neither allele Met have showed a significant association to phenotype, these results contrast the many contradictory studies published in recent years, thus generating overall result of the influence of genotype variants.