{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,4]],"date-time":"2026-06-04T18:52:14Z","timestamp":1780599134833,"version":"3.54.1"},"reference-count":34,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2019,9,25]],"date-time":"2019-09-25T00:00:00Z","timestamp":1569369600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001659","name":"Deutsche Forschungsgemeinschaft","doi-asserted-by":"publisher","award":["SFB621"],"award-info":[{"award-number":["SFB621"]}],"id":[{"id":"10.13039\/501100001659","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nutrients"],"abstract":"<jats:p>Congenital sucrase-isomaltase deficiency (CSID) is an autosomal recessive disorder of carbohydrate maldigestion and malabsorption caused by mutations in the sucrase-isomaltase (SI) gene. SI, together with maltase-glucoamylase (MGAM), belongs to the enzyme family of disaccharidases required for breakdown of \u03b1-glycosidic linkages in the small intestine. The effects of homozygote and compound heterozygote inheritance trait of SI mutations in CSID patients have been well described in former studies. Here we propose the inclusion of heterozygote mutation carriers as a new entity in CSID, possibly presenting with milder symptoms. The hypothesis is supported by recent observations of heterozygote mutation carriers among patients suffering from CSID or patients diagnosed with functional gastrointestinal disorders. Recent studies implicate significant phenotypic heterogeneity depending on the character of the mutation and call for more research regarding the correlation of genetics, function at the cellular and molecular level and clinical presentation. The increased importance of SI gene variants in irritable bowel syndrome (IBS) or other functional gastrointestinal disorders FGIDs and their available symptom relief diets like fermentable oligo-, di-, mono-saccharides and polyols FODMAPs suggest that the heterozygote mutants may affect the disease development and treatment.<\/jats:p>","DOI":"10.3390\/nu11102290","type":"journal-article","created":{"date-parts":[[2019,9,26]],"date-time":"2019-09-26T03:06:51Z","timestamp":1569467211000},"page":"2290","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["Heterozygotes Are a Potential New Entity among Homozygotes and Compound Heterozygotes in Congenital Sucrase-Isomaltase Deficiency"],"prefix":"10.3390","volume":"11","author":[{"given":"Diab M.","family":"Husein","sequence":"first","affiliation":[{"name":"Department of Physiological Chemistry, University of Veterinary Medicine Hannover, B\u00fcnteweg 17, 30559 Hannover, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dalanda","family":"Wanes","sequence":"additional","affiliation":[{"name":"Department of Physiological Chemistry, University of Veterinary Medicine Hannover, B\u00fcnteweg 17, 30559 Hannover, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lara M.","family":"Marten","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, University Medical Center Hamburg-Eppendorf, D-20246 Hamburg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Klaus-Peter","family":"Zimmer","sequence":"additional","affiliation":[{"name":"Department of General Pediatrics and Neonatology, University Medical Center Giessen and Marburg, Feulgenstr, 10-12, D-35392 Giessen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4884-8425","authenticated-orcid":false,"given":"Hassan Y.","family":"Naim","sequence":"additional","affiliation":[{"name":"Department of Physiological Chemistry, University of Veterinary Medicine Hannover, B\u00fcnteweg 17, 30559 Hannover, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2019,9,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"5735","DOI":"10.1016\/S0021-9258(19)41116-2","article-title":"Human intestinal sucrase-isomaltase. 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