Inflammation, microbiome and colorectal cancer disparity in African-Americans: Are there bugs in the genetics?

Figure 1 Immune-related variant may promote survival to pathogens in ancestral African environment but precipitate cancer in descendent African-Americans. Pathogens associated with endemic African regions (e.g., malaria) are thought to pressure selection for specific immune-related genetic variants associated with pathogen resistance and survival of Native Africans (left). In the context of westernized diet and lifestyle, this genetic predisposition (represented herein by a single nucleotide variant), when associated with inflammatory regulation and inherited from African ancestors, may lead to altered interactions with bacteria or communities of bacteria of the gut microbiome, thereby precipitating the colon adenoma-carcinoma sequence in African-Americans (right). Higher inflammation associated with lack of exercise, high fat diet, and socio-economic status are thought to be predominant factors driving early colorectal cancer onset in African-Americans via their impact on shaping the gut microbiome and its interactions with the host genetic background. SNV: Single nucleotide variant. Created with Biorender.com.