Brazilian High-Risk Cohort (BHRC)
The Brazilian High-Risk Cohort for Mental Health Conditions (BHRC) is a long-term, multi-generational study of the developmental trajectories of mental health. Since 2009, it has followed a large cohort to understand how genetic predispositions and environmental factors interact to shape neurodevelopment from childhood into adulthood. The study focuses on identifying early markers of risk and resilience for mental disorders within a diverse, middle-income country population.  The cohort is notable for its expansion to three generations: the original participants (G2), their parents (G1), and their own children (G3). This design allows for the examination of heritability and transgenerational patterns related to mental health and cognitive development.  To investigate the biological underpinnings of mental health, the BHRC has collected an extensive repository of biospecimens (including blood, saliva, and hair) from thousands of participants across multiple time points (waves). The genetic data collected from these samples support a wide range of omics analyses. This includes:  Genomic Data:  SNP-Array: Genotyping has been performed on over 2,100 G2 participants and nearly 3,000 G1 parents (Illumina Global Screening Array). An additional 720 G2 participants were also genotyped on the Illumina HumanCore Array.  Whole Genome Sequencing (WGS): High-coverage (30X) WGS data has been collected from over 2,200 G2 participants and more than 700 G1 mothers.  Telomere Length and Mitochondrial DNA: Assessments have been conducted for hundreds of G2 participants at multiple waves.  Transcriptomic Data:  Messenger RNA (mRNA) Sequencing: mRNA-seq data and targeted mRNA-seq is available from hundreds of G2 participants at both baseline and the 3-year follow-up.  Gene Expression: Additional transcriptomic data includes information from Illumina HT-12 Beadchips and RT-PCR for inflammation-related genes.  Epigenomic Data:  DNA Methylation: Genome-wide DNA methylation data (EPIC array v1.0 and v2.0) has been collected from hundreds of G2 participants across three different waves.  miRNA Sequencing: Serum-derived extracellular vesicle (EV) miRNA sequencing has also been performed.  A central feature of the BHRC is the integration of this biological data with a wide array of deep phenotypic information collected over 15 years, including:  Neuroimaging: Multi-modal MRI data (structural T1, DTI, resting-state fMRI) from four waves of scanning.  Clinical Assessments: Comprehensive diagnostic interviews for mental health conditions.  Cognitive and Behavioral Data: Extensive testing of executive function, intelligence, and temperament.  Environmental Data: Detailed information on life stressors, socioeconomic status, family environment, and education.  This combination of data allows researchers to explore the genetic architecture of mental health traits, investigate gene-environment interactions, and identify biomarkers for risk and resilience. Further details on the cohort can be found at this link: https://osf.io/ktz5h/