Emerging research groups studying Brazilian psychiatric genetics

Abstract

Emerging research groups studying Brazilian psychiatric genetics Grupos de pesquisa emergentes em estudos de genética psiquiátrica brasileiraDear Editor, In their recent paper entitled A review of psychiatric genetics research in the Brazilian population, Cordeiro et al.1 conducted an interesting review by describing the most important research groups now at work and their main findings on the Brazilian population. The authors briefly discussed relevant findings on drug addiction, alcohol dependence, pathological gambling, schizophrenia, bipolar disorder, obsessive compulsive disorder, suicidal behaviors and attention deficit hyperactivity disorder. Additionally, they argued their point of view with respect to the obstacles and challenges faced by psychiatric genetic studies considering Brazil´s heterogeneous ethnicity.Although the paper is very interesting, its authors failed to describe the methodology employed for conducting the research and, apparently, their failure in performing a systematic review resulted in they neglecting publications already available in the field. Our group has been studying anxiety and its endophenotypes, like personality traits as neuroticism, harm avoidance and behavioral inhibition 2,3 as well as suicidal behavior in depressed patients. 4,5 In brief, with respect to anxiety disorders and endophenotypes, we found no association between the serotonin transporter promoter polymorphism (5-HTTLPR) and personality traits in asymptomatic patients with panic disorder. 3 We have also described preliminary evidence of the association between EFHC2 (a gene implicated in fear recognition) and harm avoidance. In this study, an intronic single nucleotide polymorphism (SNP), rs1562875, was associated with harm avoidance, accounting, alone, for over 3% of variance in this trait. This same SNP was nominally but not empirically associated with behavior inhibition and panic disorder with an odds ratio of 2.64. 2The main results of our studies in suicidal behavior include a replication of an association between suicidal behavior and a polymorphism in the serotonin transporter gene (5-HTTLPR), demonstrating a higher risk for suicide behavior among depressed patients bearing SS or LS genotypes. 5 We also performed a reanalysis of a novel 5-HTTLPR functional variant identified within the L allele which alters its messenger RNA production.Even though our results did not replicate the association between functional 5-HTTLPR suicidal behavior in depressed patients who have attempted suicide, this was the first study to ever perform this kind of this analysis in a Brazilian population. 4 As properly emphasized by Cordeiro et al, the Brazilian population is composed of the admixture between European, African and Native American populations, a fact which raises a number of problems when performing genetic studies. In order to avoid stratification, in our studies we use more homogenous samples like the Caucasians that live in the southern state of Rio Grande do Sul, which is an area that has recently r...

The multidimensional evaluation and treatment of anxiety in children and adolescents: rationale, design, methods and preliminary findings

“…In addition, this paper aims to describe the preliminary results as well as to allow research collaboration with other emerging groups 44 that share research interests and similar research protocols. The PROTAIA Project is a promising research project that can contribute to the knowledge of the relationship between anxiety disorders and anxiety-related phenotypes with several genetic and environmental risk factors.…”