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Inflammatory bowel disease: maladaptation of the vigilant genotype in a hyper-clean world?

T V Rajan1

  • 1Department of Pathology, University of Connecticut Health Center, 263 Farmington Ave., 06032, USA. rajan@neuron.uchc.edu

Perspectives in Biology and Medicine
|May 17, 2006
PubMed

Insights

Children of Asian Indian descent raised in Western countries show increased risk for inflammatory bowel disease (IBD). This suggests "vigilant genotypes" adapted to pathogen-rich environments may trigger autoimmunity in hygienic settings.

Area of Science:

  • Immunology
  • Genetics
  • Gastroenterology

Background:

  • Children of Asian Indian heritage raised in Western nations exhibit a higher incidence of inflammatory bowel disease (IBD), including ulcerative colitis and Crohn's disease.
  • This observation parallels the NOD/Lt mouse strain, which develops autoimmune diabetes in pathogen-free conditions but not in standard environments.

Purpose of the Study:

  • To propose a hypothesis explaining the increased susceptibility to autoimmune diseases like IBD in specific populations.
  • To explore the role of
  • vigilant genotypes
  • and environmental interactions in immune dysregulation.

Main Methods:

  • Comparative analysis of disease incidence in human populations and animal models.
  • Hypothetical framework based on evolutionary genetics and immunology.

Main Results:

  • A proposed link between specific genetic profiles and increased risk for autoimmune conditions.
  • Environmental hygiene is suggested as a critical factor in the manifestation of these diseases.

Conclusions:

  • The
  • vigilant genotype
  • hypothesis offers a potential explanation for organ-specific autoimmunity.
  • Genetic predisposition combined with modern hygienic environments may lead to maladaptive immune responses and diseases such as IBD.

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