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Galactokinase deficiency

Other Names for this Disease
  • Galactosemia 2
  • GALK deficiency
  • Hereditary galactokinase deficiency
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Galactokinase deficiency, or galactosemia type 2, is a type of galactosemia that affects how the body processes a simple sugar called galactose.  A small amount of galactose is present in many foods. It is primarily part of a larger sugar called lactose, which is found in all dairy products and many baby formulas. The signs and symptoms of galactosemia result from an inability to use galactose to produce energy. Galactokinase deficiency causes fewer medical problems than the classic type. Affected infants usually develop cataracts, but otherwise experience few long-term complications. This condition is caused by mutations in the GALK1 gene and is inherited in an autosomal recessive fashion.[1]
Last updated: 6/9/2011


  1. Galactosemia. Genetics Home Reference. January 2008; Accessed 6/9/2011.
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Basic Information

  • Genetics Home Reference (GHR) contains information on Galactokinase deficiency. This website is maintained by the National Library of Medicine.
  • MedlinePlus was designed by the National Library of Medicine to help you research your health questions, and it provides more information about this topic.

In Depth Information

  • The Online Mendelian Inheritance in Man (OMIM) is an catalog of human genes and genetic disorders. Each entry has a summary of related medical articles. It is meant for health care professionals and researchers. OMIM is maintained by Johns Hopkins University School of Medicine. 
  • Orphanet is a European reference portal for information on rare diseases and orphan drugs.  Access to this database is free of charge.
  • PubMed is a searchable database of medical literature and lists journal articles that discuss Galactokinase deficiency. Click on the link to view a sample search on this topic.