Gene Mutation Linked to Congenital Diarrhea
Mutation affects differentiation of enteroendocrine cells and intestine's ability to absorb nutrients
WEDNESDAY, July 19 (HealthDay News) -- Mutations in the neurogenin-3 gene required for the development of endocrine cells in the pancreas and intestine are associated with congenital malabsorptive diarrhea, and may be responsible for a newly discovered malabsorptive disease characterized by a lack of enteroendocrine cells, according to a report in the July 20 issue of the New England Journal of Medicine.
Martin G. Martin, M.D., of the University of California Los Angeles, and colleagues screened genomic DNA from three unrelated boys who lacked intestinal enteroendocrine cells and had similar clinical characteristics, including vomiting, dehydration and chronic, unremitting, malabsorptive diarrhea in the first weeks of life.
The researchers found that the boys had two different mutations in neurogenin-3 (NEUROG3) that disrupted the protein's ability to activate the promoter of NEUROD1, a similar gene. The mutation disrupted the differentiation of intestinal absorptive cells and secretory cells.
"The clinical findings highlight a critical role of enteroendocrine cells in augmenting nutrient absorption," the authors write. "These findings may also help uncover the cause of several other associated forms of diarrhea, including diarrhea-predominant irritable bowel syndrome and various inflammatory and other forms of congenital diarrhea," they conclude.