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Published on: April 1, 2019

Association between the UGT1A1 TA-repeat polymorphism and bilirubin concentration in patients with intermittent

Barbara Rantner1, Barbara Kollerits, Marietta Anderwald-Stadler

  • 1Division of Genetic Epidemiology, Department of Medical Genetics, Molecular and Clinical Pharmacology, Innsbruck Medical University, Innsbruck, Austria.

Clinical Chemistry
|April 1, 2008
PubMed

Insights

Low bilirubin levels are linked to peripheral arterial disease in men. The UGT1A1 gene polymorphism, affecting bilirubin metabolism, was not associated with this condition in the study. Further research is needed.

Area of Science:

  • Biochemistry
  • Genetics
  • Vascular Medicine

Background:

  • Bilirubin possesses antioxidant and cytoprotective properties.
  • Low plasma bilirubin concentrations are linked to cardiovascular and cerebrovascular diseases.
  • Hepatic uridine diphosphate glucuronosyltransferase (UGT1A1) enzyme activity influences bilirubin levels and is affected by a gene polymorphism.

Purpose of the Study:

  • To investigate the association between the UGT1A1 gene polymorphism, bilirubin concentration, and intermittent claudication in male patients.
  • To explore the relationship between bilirubin levels and peripheral arterial disease.

Main Methods:

  • A case-control study involving 255 male patients with intermittent claudication and 255 matched controls.
  • Measurement of plasma bilirubin concentrations.
  • Genotyping for the UGT1A1 TA-repeat polymorphism.

Main Results:

  • Patients with intermittent claudication had significantly lower plasma bilirubin concentrations than controls.
  • A clear association was observed between the number of TA repeats in the UGT1A1 gene and plasma bilirubin concentration.
  • No significant difference in UGT1A1 TA-repeat genotype frequencies was found between patients and controls.

Conclusions:

  • Low plasma bilirubin concentrations are clearly associated with peripheral arterial disease.
  • The UGT1A1 polymorphism is not associated with intermittent claudication in this patient cohort.
  • Bilirubin's role in vascular health warrants further investigation.
Abstract

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