From Mutations to Microbes: Investigating the Impact of the Gut Microbiome on Repeat Expansion Disorders

Repeat expansion disorders (REDs) are a diverse array of genetic disorders characterized by the expansion of specific DNA sequences. These expansions are frequently dynamic and are susceptible to further expansion across generations. They contribute to disease progression by leading symptoms to become more severe and manifest earlier in subsequent generations. Despite a substantial understanding of their molecular mechanisms, the exact etiology of REDs remains tricky. Emerging evidence indicates that gut microbiome dysbiosis significantly impacts REDs by regulating various biochemical pathways. Alterations in microbial diversity and composition have been observed across multiple REDs; however, a comprehensive understanding of the complete scenario remains a significant challenge. To elucidate these dynamic interactions, future research should utilize multifaceted approaches. This review focuses on the key modifications in the gut microbiome that contribute to the pathogenesis of REDs and discusses potential gut microbiome-targeted therapeutic strategies that could be effectively employed to treat these disorders.