The genetic relationships between post-traumatic stress disorder and its corresponding neural circuit structures

Area of Science:

• Neurogenetics
• Psychiatric Disorders
• Brain Imaging Genetics

Background:

• Post-traumatic stress disorder (PTSD) involves neural circuit abnormalities in fear processing.
• The genetic contribution to PTSD's neural circuit alterations remains unclear.
• Understanding genetic links is crucial for PTSD etiology and treatment.

Purpose of the Study:

• To investigate the genetic association between PTSD and brain circuitry components.
• To identify specific brain regions and genetic loci implicated in PTSD.
• To explore potential causal relationships between PTSD and brain structure.

Main Methods:

• Meta-analysis of PTSD genome-wide association studies (GWAS) from 306,400 individuals.
• Analysis of genetic associations with 9 brain structure traits (cortical, subcortical, white matter).
• Utilized heritability enrichment, genetic correlation, polygenic overlap, and causal inference methods.

Main Results:

• Heritability enrichment for PTSD found in circuitry-relevant regions: cingulate and frontal cortex.
• Identified significant genetic correlations between PTSD and these brain regions.
• Discovered 31 novel genetic loci (conjunction FDR < 0.05) linked to DNA repair and neurodegeneration pathways, with a potential causal link between PTSD and frontal pole surface area.

Conclusions:

• Genetic factors significantly contribute to PTSD's impact on specific brain circuits.
• Novel genetic loci associated with PTSD implicate DNA repair and neurodegeneration.
• Findings provide insights into PTSD's genetic underpinnings and its relationship with brain structure, particularly the frontal pole.