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Galactokinase Deficiency Clinical Presentation

  • Author: Karl S Roth, MD; Chief Editor: Maria Descartes, MD  more...
Updated: Sep 08, 2015


Hepatosplenomegaly at birth (reported in a single case) is not common in neonates with galactokinase deficiency.

Failure to develop a social smile or to follow objects may represent initial signs of a visual deficit due to cataracts.

GI symptoms associated with the ingestion of galactose are conspicuously absent.

Growth parameters are unaffected.

Family history is not relevant.

Soy formula (given to the infant for other reasons) may curtail the development of cataracts and delay the consequent diagnosis of galactokinase deficiency. However, milk products introduced into the diet later will result in cataract formation.



Cataracts may be apparent upon gross inspection of the eye.

Opacities may be visualized during attempts at funduscopic examination.

Vision-based developmental landmarks, such as tracking, reaching, and social smiling, may be reached late or not at all.



Galactokinase deficiency is an autosomal recessive genetic disorder mapped to band 17q24.

At least 20 mutations are known. The P28T mutation is considered the founder mutationin Romani families from southeastern Europe.[5]

Many genetic variations of GALK1 have been identified in the patients with galactokinase deficiency.[6, 7]

Contributor Information and Disclosures

Karl S Roth, MD Retired Professor and Chair, Department of Pediatrics, Creighton University School of Medicine

Karl S Roth, MD is a member of the following medical societies: Alpha Omega Alpha, American Academy of Pediatrics, American College of Nutrition, American Pediatric Society, American Society for Nutrition, American Society of Nephrology, Association of American Medical Colleges, Medical Society of Virginia, New York Academy of Sciences, Sigma Xi, Society for Pediatric Research, Southern Society for Pediatric Research

Disclosure: Nothing to disclose.

Specialty Editor Board

Mary L Windle, PharmD Adjunct Associate Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference

Disclosure: Nothing to disclose.

Eric T Rush, MD, FAAP, FACMG Clinical Geneticist, Munroe-Meyer Institute for Genetics and Rehabilitation; Assistant Professor of Pediatrics and Internal Medicine, University of Nebraska Medical Center

Eric T Rush, MD, FAAP, FACMG is a member of the following medical societies: American Academy of Pediatrics, American College of Medical Genetics and Genomics, American College of Physicians, Nebraska Medical Association

Disclosure: Serve(d) as a speaker or a member of a speakers bureau for: Alexion Pharmaceuticals<br/>Honoraria for: Alexion Pharmaceuticals and Biomarin Pharmaceuticals.

Chief Editor

Maria Descartes, MD Professor, Department of Human Genetics and Department of Pediatrics, University of Alabama at Birmingham School of Medicine

Maria Descartes, MD is a member of the following medical societies: American Academy of Pediatrics, American College of Medical Genetics and Genomics, American Medical Association, American Society of Human Genetics, Society for Inherited Metabolic Disorders, International Skeletal Dysplasia Society, Southeastern Regional Genetics Group

Disclosure: Nothing to disclose.

Additional Contributors

Michael Fasullo, PhD Senior Scientist, Ordway Research Institute; Associate Professor, State University of New York at Albany; Adjunct Associate Professor, Center for Immunology and Microbial Disease, Albany Medical College

Michael Fasullo, PhD is a member of the following medical societies: Radiation Research Society, American Society for Biochemistry and Molecular Biology, Genetics Society of America, Environmental Mutagenesis and Genomics Society

Disclosure: Nothing to disclose.

  1. Cuthbert C, Klapper H, Elsas L. Diagnosis of inherited disorders of galactose metabolism. Curr Protoc Hum Genet. 2008 Jan. Chapter 17:Unit 17.5. [Medline].

  2. Janzen N, Illsinger S, Meyer U, Shin YS, Sander J, Lücke T, et al. Early cataract formation due to galactokinase deficiency: impact of newborn screening. Arch Med Res. 2011 Oct. 42(7):608-12. [Medline].

  3. Hennermann JB, Schadewaldt P, Vetter B, Shin YS, Mönch E, Klein J. Features and outcome of galactokinase deficiency in children diagnosed by newborn screening. J Inherit Metab Dis. 2011 Apr. 34(2):399-407. [Medline].

  4. The University of Texas Health Science Center at San Antonio. National newborn screening status report. Updated 01/06/13. Available at Accessed: April 14, 2014.

  5. Kalaydjieva L, Perez-Lezaun A, Angelicheva D, et al. A founder mutation in the GK1 gene is responsible for galactokinase deficiency in Roma (Gypsies). Am J Hum Genet. 1999 Nov. 65(5):1299-307. [Medline]. [Full Text].

  6. Park HD, Kim YK, Park KU, Kim JQ, Song YH, Song J. A novel c.-22T>C mutation in GALK1 promoter is associated with elevated galactokinase phenotype. BMC Med Genet. 2009 Mar 24. 10:29. [Medline]. [Full Text].

  7. Park HD, Bang YL, Park KU, Kim JQ, Jeong BH, Kim YS, et al. Molecular and biochemical characterization of the GALK1 gene in Korean patients with galactokinase deficiency. Mol Genet Metab. 2007 Jul. 91(3):234-8. [Medline].

  8. Berry GT. The role of polyols in the pathophysiology of hypergalactosemia. Eur J Pediatr. 1995. 154(7 Suppl 2):S53-64. [Medline].

  9. Beutler E, Matsumoto F, Kuhl W, Krill A, Levy N, Sparkes R, et al. Galactokinase deficiency as a cause of cataracts. N Engl J Med. 1973 Jun 7. 288(23):1203-6. [Medline].

  10. Bosch AM, Bakker HD, van Gennip AH, van Kempen JV, Wanders RJ, Wijburg FA. Clinical features of galactokinase deficiency: a review of the literature. J Inherit Metab Dis. 2002 Dec. 25(8):629-34. [Medline].

  11. Gitzelmann R. Hereditary galactokinase deficiency, a newly recognized cause of juvenile cataracts. Pediatr Res. 1967. 1:14-23.

  12. Hunter M, Heyer E, Austerlitz F. The P28T mutation in the GALK1 gene accounts for galactokinase deficiency in Roma(Gypsy) patients across Europe. Pediatr Res. 2002. 51:602-606.

  13. Kerr MM, Logan RW, Cant JS, Hutchison JH. Galactokinase deficiency in a newborn infant. Arch Dis Child. 1971 Dec. 46(250):864-6. [Medline].

  14. Levy NS, Krill AE, Beutler E. Galactokinase deficiency and cataracts. Am J Ophthalmol. 1972 Jul. 74(1):41-8. [Medline].

  15. Pickering WR, Howell RR. Galactokinase deficiency: clinical and biochemical findings in a new kindred. J Pediatr. 1972 Jul. 81(1):50-5. [Medline].

  16. Reich S, Hennerman J, Vetter B. An unexpectedly high frequency of hypergalactosemia in an immigrant Bosnian population revealed by newborn screening. Pediatr Res. 2002. 51:598-601.

  17. Sangiuolo F, Magnani M, Stambolian D. Biochemical characterization of two GALK1 mutations in patients with galactokinase deficiency. Hum Mutat. 2004. 23:396.

  18. Thalhammer O, Gitzelmann R, Pantlitschko M. Hypergalactosemia and galactosuria due to galactokinase deficiency in a newborn. Pediatrics. 1968 Sep. 42(3):441-5. [Medline].

UDP-galactose synthesis and galactosemia. The most common form of galactosemia is due to a deficiency of galactose-1-phosphate uridyltransferase (GALT). This enzyme normally uses galactose-1-phosphate derived from dietary galactose. In the absence of GALT, galactose-1-phosphate accumulates, along with excessive galactose and its oxidative and reductive products galactitol and galactonate (not shown). UDP-galactose synthesis may also be impaired in the absence of GALT but not completely because UDP-galactose-4′-epimerase (GALE) can form UDP-galactose from UDP-glucose and can supply the donor to galactosyltransferases required for normal glycoconjugate biosynthesis.
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