Mutation analysis in Turkish patients with hereditary fructose intolerance A.DURSUN 1 *,H.S.KALKANO  GLU 1 ,T.COS ;KUN 2 ,A.TOKATLI 1 ,R.BITTNER 3 , N.KOC°AK 2 ,A.YU « CE 2 ,I.OZALP 1 ,andH.-J.BOEHME 3 Hacettepe University School of Medicine, 1 Department of Pediatrics, Metabolism and Nutrition Unit, 2 Department of Pediatrics, Gastroenterology Unit, Ankara, Turkey; 3 Leipzig University Institute of Biochemistry, Leipzig, Germany * Correspondence: Hacettepe University School of Medicine, Department of Pediatrics, Metabolism and Nutrition Unit, 06100 Ankara, Turkey. E-mail: adursun@hacettepe.edu.tr MS received 22.01.01 Revised and accepted 22.05.01 Summary: ThirteenTurkishpatientswithhereditaryfructoseintolerance(HFI) werescreenedforthethreecommonmutations,A149P,A174DandN334K,in thealdolaseBgenethathavebeendetectedfrequentlyinEuropeanpopulation. WefoundthatnineofthepatientscarrytheA149Pmutationinbothalleles, whichcorrespondstoafrequencyofabout55%.Single-strandconformation analysisofallcodingexonsofthegenewasalsoperformedtodetectunknown mutations in four patients not carrying the three common mutations. No aberrantmigrationpatternswereobservedinthesepatients. Hereditary fructose intolerance (HFI) is an autosomal recessive disease caused by de¢ciencyofaldolaseB(McKusick229600,EC2.1.2.13).Thepatientspresentwith vomiting, abdominal pain, hypoglycaemia, hypophosphataemia, acidosis and fructosuria after ingestion of fructose and related sugars. Affected patients usually develop an aversion to fructose-containing foods and drinks. Growth retardation may be encountered in many patients even after a restriction of dietary fructose. TherapeuticprotocolinHFIconsistsofstringentlimitationoffructoseintakeand avoidanceofprolongedfasting(Gitzelmanetal1995).ThealdolaseBgene,which consistsofnineexons,mapstochromosome9q22.3andthecognatemRNAencodes for364aminoacids(Rottmanetal1984;TolanandPenhoet1986).Sincethe¢rst ¢ndingsofdisease-causingmutationsin1988(Crossetal1988),morethantwenty mutations have been described and registered in the Human Gene Mutation Database^Cardiff (HGMD Cardiff). The missense mutations A149P, A174D and N334KhavebeenfoundtobethemostprevalentintheEuropeanpopulation(Cross J. Inherit. Metab. Dis. 24(2001)523^526 # SSIEMandKluwerAcademicPublishers.PrintedintheNetherlands. 523