Systematic exploration of a decade of publications on psychiatric genetics in Latin America.

Psychiatric disorders have a great impact in terms of mortality, morbidity, and disability across the lifespan. Considerable effort has been devoted to understanding their complex and heterogeneous genetic architecture, including diverse ancestry populations. Our aim was to review the psychiatric genetics research published with Latin American populations from 2010 to 2019, and classify it according to country of origin, type of analysis, source of funding, and other variables. We found that most publications came from Brazil, Mexico, and Colombia. Also, local funds are generally not large enough for genome-wide studies in Latin America, with the exception of Brazil and Mexico; larger studies are often done in collaboration with international partners, mostly funded by US agencies. In most of the larger studies, the participants are individuals of Latin American ancestry living in the United States, which limits the potential for exploring the complex gene-environment interaction. Family studies, traditionally strong in Latin America, represent about 30% of the total research publications. Scarce local resources for research in Latin America have probably been an important limitation for conducting bigger and more complex studies, contributing to the reduced representation of these populations in global psychiatric genetics studies. Increasing diversity must be a goal to improve generalizability and applicability in clinical settings.

Underlying domains of anxiety trait in a Costa Rican sample: preliminary results.

BACKGROUND: Imprecision of the psychiatric phenotype might partially explain the failure of genetic research to identify genes that contribute to susceptibility of anxiety disorders. Previous research concluded two underlying constructs, worry and rumination, might explain anxiety sub-syndromic symptoms in Costa Rican patients with history of mania. The goal of the current study is to explore the presence of latent constructs for quantitative anxiety in a group of subjects with a wide diagnostic phenotype and non-affected individuals. METHODS: We conducted an exploratory factor analysis of anxiety trait in 709 subjects. Our sample was comprised by 419 subjects with psychiatric disorders and 290 non-affected individuals. We used principal factors extraction method with squared multiple correlations of the STAI (trait subscale). RESULTS: We found the following preliminary results: a three-factor solution with a good simple structure and statistical adequacy was obtained with a KMO of 0.92 (>0.6) and Bartlett's Test of Sphericity of 5644,44 (p<0.05). The STAI items were grouped into three factors: anxiety-absent, worry and rumination based on the characteristics of the symptoms. CONCLUSION: Two underlying constructs, worry and rumination may explain anxiety sub-syndromic symptoms in Costa Rican subjects. Our proposed underlying structure of subsyndromal anxiety in individuals should be considered as an important factor in defining better phenotypic characterizations on a broader diagnostic concept. Worry and rumination as a phenotypic characterization may assist in genotyping; however, its predictive value on actual illness outcome still requires more research. The Genome-Wide QTL analysis for anxiety trait in the same sample is ongoing.