Abstract

This study explored the association between serotonin transporter gene (5HTTLPR) and brain-derived neurotrophic factor gene (BDNF) polymorphisms with mental health disorders in a Chilean primary care population using latent class analysis. The sample included 789 adults genotyped for 5HTTLPR and BDNF, who were assessed for psychiatric diagnoses using the Composite International Diagnostic Interview (CIDI). Two distinct mental health profiles emerged: a high psychiatric comorbidity group, marked by a high prevalence of anxiety and stress-related disorders, and a low comorbidity group. The study found that the L'/L' polymorphism of the serotonin transporter gene was associated with a reduced risk of belonging to the high-comorbidity group, particularly when paired with the GG polymorphism of the BDNF gene. These findings suggest a synergistic interaction between these genes that influences susceptibility to psychiatric disorders. This research underscores the importance of considering genetic interactions in mental health studies and highlights the utility of latent class analysis in identifying clinically relevant diagnostic profiles, which could enhance early detection and intervention strategies in primary care.