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Human Genetics

, Volume 93, Issue 2, pp 167–169 | Cite as

On the molecular nature of the Duarte variant of galactose-1-phosphate uridyl transferase (GALT)

  • Hsien-Chin Lin
  • Lorne T. Kirby
  • Won G. Ng
  • Juergen K. V. Reichardt
Original Investigations

Abstract

Galactosemia is an inborn error of galactose metabolism secondary to deficiency of galactose-1-phosphate uridyl transferase (GALT). GALT is a polymorphic enzyme and Duarte (D) is the most common enzyme variant. This variant is characterized by faster electrophoretic mobility and reduced activity. Duarte/galactosemia compound heterozygotes (D/G) are commonly identified in galactosemia newborn screening programs. However, these patients do not generally require treatment. By using a “candidate mutation” approach to define the molecular basis of the Duarte variant of GALT, a close association between the previously reported N314D polymorphism and the Duarte variant of GALT was found. We suggest that N314D encodes the D variant of GALT and that molecular testing for N314D might be useful to confirm a biochemical diagnosis of Duarte variant of GALT.

Keywords

Galactose Screening Program Electrophoretic Mobility Newborn Screening Inborn Error 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag 1994

Authors and Affiliations

  • Hsien-Chin Lin
    • 1
  • Lorne T. Kirby
    • 3
  • Won G. Ng
    • 4
  • Juergen K. V. Reichardt
    • 1
    • 2
  1. 1.Department of Biochemistry and Molecular BiologyUniversity of Southern California School of MedicineLos AngelesUSA
  2. 2.Institute for Genetic Medicine, University of Southern California School of MedicineLos AngelesUSA
  3. 3.Division of PathologyChildren's HospitalVancouverCanada
  4. 4.Division of Medical GeneticsChildrens' Hospital Los AngelesLos AngelesUSA

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