Pseudodominant Transmission of Fructose Intolerance in an Adult and Three Offspring: Heterozygote Detection by Intestinal Biopsy

HEREDITARY fructose intolerance is an inborn error of metabolism characterized by abdominal pain, vomiting, and hypoglycemia, which follow the ingestion of fructose.¹ The disorder is associated with a deficiency of aldolase B in the liver, kidney, and intestinal mucosa.^{2 3 4} Although fructose intolerance is generally regarded as an autosomal recessive condition, transmission of overt disease from parents to offspring in a few nonconsanguineous families has suggested the possibility of genetic heterogeneity.^1,5,6 However, the exact mode of inheritance cannot be defined in the absence of suitable methods to detect putative heterozygotes.^{7 8 9} We report studies in an unusual family with fructose intolerance in.