OMIM ID:
Fructose Intolerance
Alternate Names
Defective Genes
Clinical Characteristics
Ocular Features
Dense cataracts have been reported in the first decade of life in several patients.
Systemic Features
Abdominal pain, vomiting and hypoglycemia usually appears in infancy upon the introduction of fructose or sucrose to the diet. Some infants have a more severe reaction to such sugars with lethargy, seizures and coma. Older children and adults develop a protective aversion to fruits and sweets. Chronic ingestion leads to liver cirrhosis, renal tubule damage, growth retardation, and even malnutrition. Adults may also have hypoglycemia and metabolic acidosis when challenged with sucrose and fructose.
Genetics
Inheritance
Pedigree
Autosomal recessive
In order for autosomal recessive disorders to be expressed, offspring generally must inherit two mutations, one from each carrier parent. Carriers with only one mutation, such as the parents, do not have clinical disease. Note that carrier parents can expect that 1 in 4 children (25%) will inherit both mutations and have the disorder, 2 in 4 children (50%) will be carriers like their parents, while 1 in 4 children (25%) inherit neither mutation.
In order for autosomal recessive disorders to be expressed, offspring generally must inherit two mutations, one from each carrier parent. Carriers with only one mutation, such as the parents, do not have clinical disease. Note that carrier parents can expect that 1 in 4 children (25%) will inherit both mutations and have the disorder, 2 in 4 children (50%) will be carriers like their parents, while 1 in 4 children (25%) inherit neither mutation.