Rare Hypomorphic Sucrase Isomaltase Variants in Relation to Irritable Bowel Syndrome Risk in UK Biobank

Abstract excerpt

Sucrase-isomaltase (encoded by the SI gene) is the major intestinal brush border enzyme primarily responsible for the digestion of starch and sucrose.1 As seen in patients with congenital SI deficiency (a rare form of sucrose intolerance due to recessive mutations in the SI gene), inactive SI leads to colonic accumulation of unabsorbed carbohydrates, causing osmotic diarrhea, abdominal pain, and bloating.2,3...