Sucrase-isomaltase genotype and response to a starch-reduced and sucrose-reduced diet in IBS-D patients

Recently in Gut, several reviews and reports have highlighted hypomorphic (dysfunctional) variants of the sucrase-isomaltase (SI) gene in relation to increased risk of irritable bowel syndrome (IBS), particularly the diarrhoea-predominant type (IBS-D).1–4 Similar to congenital (rare recessive) and acquired forms of SI deficiency, impaired SI enzymatic activity is expected to lead to colonic accumulation of undigested disaccharides, thus triggering IBS manifestations via gut microbiota fermentation, gas production and osmotic diarrhoea. Reduced efficacy of a diet low in FODMAPs (fermentable oligosaccharides, disaccharides, monosaccharides and polyols) is also observed for SI hypomorphic IBS-D carriers,4 as this intervention may be suboptimal for individuals with possible defects in the digestion of carbohydrates other than FODMAPs (the lowFODMAP diet does not specifically restrict sucrose and starch, the substrates of SI disaccharidase activity). These results hold strong potential for personalising therapeutic (dietary) interventions in subgroups...

Source: Gut - March 7, 2024 Category: Gastroenterology Authors: Zamfir-Taranu, A., Löscher, B.-S., Husein, D. M., Hoter, A., Garcia-Etxebarria, K., Etxeberria, U., Gayoso, L., Mayr, G., Nilholm, C., Gustafsson, R. J., Ozaydin, O., Zheng, T., Esteban-Blanco, C., Bozzarelli, I., Bonfiglio, F., Rizk, S., Franke, Tags: Open access, Gut PostScript Source Type: research