B. Koppelt et al., MOLECULAR BIOLOGICAL INVESTIGATION IN A F AMILY WITH HEREDITARY FRUCTOSE INTOLERANCE AND DIAGNOSTIC CONSEQUENCES, Monatsschrift fur Kinderheilkunde, 144(4), 1996, pp. 383-386
Background: Advances in molecular diagnostics give rise to a reconside
ration of the diagnostic strategy in hereditary fructose intolerance,
In a family with hereditary fructose intolerance and a well documented
index patient the diagnostic procedure is demonstrated with a male br
east-fed infant. Methods: The detection of the most common point mutat
ion A149P in the aldolase B gene of this family was performed by ampli
fication of exon V and cleavage of the PCR product with the restrictio
n endonuclease AhaII. In addition, the defect in exon V was demonstrat
ed by SSCP (single strand conformational polymorphism) analysis. Resul
ts: By means of these methods, the homozygotic occurrence of this muta
tion in the patient could be proved. Additional diagnostic arrangement
s were abandoned. To our knowledge is this the very first example that
a patient with hereditary fructose intolerance was reliably diagnosed
although he was fed fructose free and had never shown any signs of a
metabolic disturbances. Conclusions: Therefore, we propose, that when
a hereditary fructose intolerance is suspected from the nutritional hi
story and the clinical picture, at first molecular biological methods
should be used for the search for mutations in the aldolase B gene, In
vasive procedures such as fructose tolerance test or liver biopsy shou
ld be applied only if the molecular biological approach has failed.