Genetic variants associated with Crohn's disease

Sonia Michail, Gilberto Bultron, R William Depaolo, Sonia Michail, Gilberto Bultron, R William Depaolo

Abstract

Crohn's disease is an immune-related disorder characterized by inflammation of the gastrointestinal mucosa, which can occur in any area throughout the digestive tract. This life-long disease commonly presents with abdominal pain, diarrhea, vomiting, and weight loss. While the exact etiology of this disease is largely unknown, it is thought to arise from an interaction between microbial, immunological, and environmental factors in a genetically susceptible host, whereby the immune system attacks the intestine as it cross reacts against gut microbial antigens. The study of genetic variants associated with Crohn's disease has shed light on our understanding of disease pathophysiology. A large number of genetic variants identified in Crohn's disease are related to genes targeting microbial recognition and bacterial wall sensing, the most common being NOD2/CARD15 gene. This review will discuss the recent advance in our knowledge of genetic variants of this disease and how they influence the disease course and prognosis.

Keywords: Crohn’s disease; autophagy; genetics.

Figures

Figure 1
Figure 1
Genes of the autophagy pathway implicated in Crohn’s disease susceptibility. Notes: There are several phases in the autophagic pathway. Initiation is the formation of the preautophagolysosome, elongation, maturation, followed by fusion of the lysosome and degradation of the cargo. Abbreviations: LRRK2, leucine-rich repeat kinase 2; IRGM, immunity-related GTPase family M protein; NOD2, nucleotide-binding oligomerization domain-containing protein 2; CARD15, caspase recruitment domain-containing protein 15; ATG16L1, autophagy-related protein 16–1; GTP, guanosine triphosphate; ULK1, serine/threonine kinase.

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