European Journal of Clinical Pharmacology

, 65:257

Distribution of TPMT risk alleles for thioupurine toxicity in the Israeli population

  • Edna Efrati
  • Lior Adler
  • Norberto Krivoy
  • Eli Sprecher
Pharmacogenetics

DOI: 10.1007/s00228-008-0590-7

Cite this article as:
Efrati, E., Adler, L., Krivoy, N. et al. Eur J Clin Pharmacol (2009) 65: 257. doi:10.1007/s00228-008-0590-7

Abstract

Background and objective

Individuals with intermediate or no thiopurine S-methyltransferase (TPMT) activity are at risk of hematotoxicity when treated with standard doses of thiopurines, thus, pretreatment identification of these individuals is of major importance. The purpose of this study was to determine the frequency and distribution of TPMT polymorphic variants, known to functionally impair TPMT activity, in the highly heterogeneous Israeli population.

Methods

TPMT genotyping of individuals representing three major demographic groups in Israel was carried out by PCR restriction fragment length polymorphism and high-resolution melting.

Results

Frequencies of TPMT risk alleles differed significantly among the screened Israeli subpopulations: Druze showed fivefold and twofold higher frequencies than Jews and Moslems, respectively. Specifically, allelic frequencies of TPMT*3A were 0.73% (95% CI 0.34-1.45%), 0.79% (95% CI 0.16-2.39%), and 3.19% (95% CI 1.78-5.58%) in Jews, Moslems, and Druze, respectively. Although not found in Jews, TPMT*3C was found at an allelic frequency of 1.05% (95% CI 0.31-2.76%) and 0.75% (95% CI 0.02-2.84%) in Moslems and Druze. TPMT*2 and TPMT*3B were not detected in any of the Israeli subpopulations studied.

Conclusion

These data indicate that the Israeli population displays a distinct TPMT genetic variability that is comprised of a mix of three major genetically diverse subpopulations, each with its unique TPMT allelic frequency distribution pattern and likelihood of developing an adverse reaction to thiopurine drugs.

Keywords

TPMTThiopurinePharmacogeneticPolymorphismMyelosupressionAzathioprine

Copyright information

© Springer-Verlag 2008

Authors and Affiliations

  • Edna Efrati
    • 1
  • Lior Adler
    • 1
  • Norberto Krivoy
    • 2
  • Eli Sprecher
    • 1
  1. 1.Center for Translational Genetics, B. Rappaport Institute for Research in the Medical Sciences, Faculty of MedicineTechnion - Israel Institute of Technology and Rambam Health Care CampusHaifaIsrael
  2. 2.Clinical Pharmacology Institute, Division of Medicine, Rambam Health Care Campus, B. Rappaport Institute for Research in the Medical Sciences, Faculty of MedicineTechnion - Israel Institute of Technology HaifaHaifaIsrael