HFI Laboratory at Boston University

HFI Incidence Rate

The world-wide incidence rate of HFI remains unknown due to the difficulty of HFI diagnosis. The first report of an incidence rate was from Switzerland, where over a five year period that included 100,000 births, five cases of HFI were reported (1). The degree of deviation in this estimate of 1 in 20,000 births is large and the incidence rate may range from 1 in 10,000 to 1 in 100,000. A more recent study in the UK using DNA testing indicated a more precise incidence rate of 1 in 22,000 where the range would be between 1 in 12,000 to 1 in 58,000 (2).

It is likely that the incidence rate varies quite widely among different ethnic groups. Until easier and more effective methods of diagnosis are available from research involving different ethnic groups, the incidence rate will remain unclear (3). There have been numerous reports of self diagnosis in adulthood, inadvertent deaths to undiagnosed subjects, and homozygous-heterozygous marriages, all of which indicate that the incidence rate could be closer to 1 in 10,000 (4, 5, 6; C. Brooks and D. Tolan, unpublished data). If so, the carrier frequency would be 1 in 50. While the frequency of HFI in Switzerland is considered by many pediatricians to be higher than other parts of the world, the reports outlined above have occurred world-wide and the presumption that HFI is a rare disorder is clearly premature.


1. Gitzelmann, R. and Baerlocher, K. (1973) Vorteile und Nachteile der Frucose in der Nahrung. Padiat. Fortbildk. Praxis 37, 40-55.

2. James, C.L., Rellos, P., Ali, M., Heeley, A.F., and Cox, T.M. (1996) Neonatal screening for HFI: frequency of the most common mutant aldolase B allele (A149P) in the British population. J. Med. Genet. 33, 837-841.

3. Tolan, D.R. (1995) Molecular Basis of Hereditary Fructose Intolerance: mutations and polymorphisms in the human aldolase B gene. Hum. Mutat. 6, 210-218.

4. Cox, T.M. (1993) Iatrogenic deaths in hereditary fructose intolerance. Arch. Dis. Childhood 69, 423-415.

5. Cox, T.M., Camilleri, M., O'Donnell, M.W., and Chadwick, V.S. (1982) Pseudodominant transmission of fructose intolerance in an adult and three offspring. Heterozygote detection by intestinal biopsy. N Engl. J. Med. 307, 537-540.

6. Barry, R.G.G., St. Colum, S. and Magner, J.W. (1968) Hereditary fructose intolerance in parent and child. J. Irish Med. Assoc. 61, 308-310.

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