SNP Shot: Genomic Insights

Congenital sucrase-isomaltase deficiency (CSID) is a genetic condition that impairs the digestion of specific sugars. Individuals with CSID struggle to digest sucrose and maltose. These sugars are disaccharides, meaning they consist of two simpler sugar units. Sucrose, common in fruits and table sugar, breaks down into glucose and fructose. Maltose, found in grains, breaks down into two glucose molecules. In CSID, the body cannot properly break down sucrose, maltose, or other carbohydrates derived from them.

Symptoms of CSID typically emerge when infants begin eating fruits, juices, grains, and other carbohydrate-rich foods after weaning. Consumption of sucrose or maltose in individuals with CSID often leads to abdominal cramps, bloating, increased flatulence, and diarrhea. These digestive issues can result in inadequate weight gain and growth (failure to thrive) and malnutrition.

Inheritance:

CSID follows an autosomal recessive inheritance pattern. This means that an individual must inherit a mutated copy of the gene from both parents to develop the condition. Each parent of someone with CSID carries one copy of the altered gene, but they usually do not exhibit any symptoms of the disorder.