Genomic Studies of Suicidal Thoughts and Behaviors in Latin American Populations: A Systematic Review

Abstract

BACKGROUND: Suicide is a leading cause of death globally, with disproportionately rising rates in Latin America. Despite increasing global interest in the biology of suicidal behavior, Latin American and Hispanic/Latinx populations remain underrepresented in genomic research. This systematic review synthesized current evidence on genomic studies of suicidality in these populations. METHODS: We reviewed molecular studies of suicidal ideation, suicide attempt, nonsuicidal self-injury, or suicide death among Latin American or Hispanic/Latinx participants (PROSPERO registration: CRD42023416616). Eligible studies examined family risk, genetic, epigenetic, or transcriptomic markers. Searches were conducted in PubMed, SciELO, REDALyC, and regional journals. Synthesis used a narrative approach and random-effects meta-analyses when feasible. Risk of bias was assessed using the Newcastle-Ottawa Scale and the Q-Genie tool. A co-authorship network analysis was performed to characterize collaboration patterns. RESULTS: Fifty-nine studies met inclusion criteria: three family, 50 genetic, six transcriptomic, and three epigenetic studies (categories not mutually exclusive). Candidate gene studies mainly examined serotonergic and stress-response pathways but yielded inconsistent results. Meta-analyses for TPH1 (rs1800532), HTR2A rs6313 (T102C), and 5-HTTLPR (rs25531) showed no significant associations. Recent genome-wide and polygenic score studies identified ancestry-specific loci, though small samples and limited functional annotation resources hindered follow-up. Transcriptomic and epigenetic studies implicated neurodevelopmental and immune-related processes. Collaboration networks were dominated by a single hub, with limited cross-group integration. CONCLUSIONS: Genomic research on suicidality in Latin America is growing but remains fragmented and underpowered. Increasing representative sampling, implementing ancestry-aware methods, and fostering collaborations are essential to advance research and inform prevention strategies in these populations.