The Real Cause of SIBO — Why Everything You’ve Been Told Is Incomplete — Genetic Predisposition: Who Gets SIBO and Why

One of the most important aspects of SIBO that is almost never discussed is the genetic architecture that determines why the same environmental exposures &#8212; a bout of food poisoning, a year on PPIs, a period of high stress &#8212; produce chronic SIBO in one person and a transient nuisance in another. Genetics does not cause SIBO directly. But genetics determines the thresholds at which each barrier fails, the severity of the failure when it occurs, and the degree to which the host can repair and recover. Understanding your genetic architecture is central to understanding your individual SIBO pattern. Here are the most clinically relevant genetic variants in SIBO, organized by the system they affect. Motility and ENS genetics: TLR4 variants affect pathogen recognition efficiency and determine the magnitude of the immune response to CdtB during gastroenteritis &#8212; which in turn determines the severity of the molecular mimicry autoimmune response to vinculin. Patients with TLR4 variants that produce exaggerated pathogen responses are more likely to develop severe post-infectious MMC damage from the same gastroenteritis exposure. IL-10 variants affect anti-inflammatory resolution capacity. IL-10 is the primary brake on the autoimmune response after infection. Patients with IL-10 variants that reduce cytokine production or signaling maintain the anti-vinculin autoimmune at