Integrating genomics with the gut-brain axis: current evidence in autism spectrum disorder, epilepsy, schizophrenia, and emerging future challenges

The relationship between the gut microbiota and the central nervous system has gained attention as a biological axis that may influence the development of several neurological disorders. Recent evidence integrating genomic, neurobiological, and microbiota research shows how bacterial composition, host genetic variability, and the mechanisms of the microbiota-gut-brain axis interact in conditions such as autism spectrum disorder, epilepsy, and schizophrenia. These interactions function through neural, metabolic, and immunological related pathways involving intestinal and blood-brain barrier permeability. Genome-wide association studies (GWAS) and Mendelian randomization analyses highlight shared immunogenetic pathways that may shape both microbial profiles and neurological susceptibility. Consistent patterns of dysbiosis and alterations in neuroactive metabolites have also been reported, linking microbiota changes to neuroinflammation and disrupted neuronal signaling. This review synthesizes the current evidence supporting the integration of the microbiota-gut-brain axis and its underlying communication pathways. It also outlines the present therapeutic strategies for neurological disorders such as autism spectrum disorder, epilepsy, and schizophrenia, highlighting their potential to modulate neurological function. Additionally, it discusses the existing limitations in the field and offers insights into future research directions within this rapidly evolving area.