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DOOR syndrome: deficiency of E1 component of the 2-oxoglutarate dehydrogenase complex

Sankar Surendran1, Kimberlee Michals-Matalon, Stephan Krywawych

  • 1Department of Pediatrics, University of Texas Medical Branch, Galveston, Texas 77555, USA.

American Journal of Medical Genetics
|November 29, 2002
PubMed

Insights

This study identifies a key biochemical marker for DOOR syndrome. Reduced 2-oxoglutarate decarboxylase (E1(0)) activity in patients

Area of Science:

  • Genetics
  • Biochemistry
  • Rare Diseases

Background:

  • DOOR syndrome is a rare genetic disorder characterized by onycho-osteodystrophy, dystrophic thumbs, sensorineural deafness, and elevated urinary 2-oxoglutarate.
  • The autosomal recessive form of DOOR syndrome has been linked to metabolic disturbances, but a specific biochemical marker was lacking.

Purpose of the Study:

  • To investigate the role of 2-oxoglutarate decarboxylase (E1(0)) activity in patients with the autosomal recessive form of DOOR syndrome.
  • To determine if E1(0) deficiency can serve as a biochemical marker for this condition.

Main Methods:

  • Enzyme activity assays were performed on fibroblasts and white blood cells from four patients across three families diagnosed with DOOR syndrome.
  • Activity levels of 2-oxoglutarate decarboxylase (E1(0)) were compared between patients and healthy controls.

Main Results:

  • Significantly decreased activity of 2-oxoglutarate decarboxylase (E1(0)) was observed in the fibroblasts and white blood cells of all DOOR syndrome patients.
  • E1(0) activity in patients was markedly lower compared to control subjects.

Conclusions:

  • This study establishes that E1(0) deficiency is a significant biochemical marker for the autosomal recessive form of DOOR syndrome.
  • Identifying E1(0) deficiency aids in the diagnosis and understanding of the metabolic basis of DOOR syndrome.

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