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CYP2C19 and ABCB1 gene polymorphisms are differently distributed according to ethnicity in the Brazilian general

Paulo C J L Santos1, Renata A G Soares, Diogo B G Santos

  • 1Laboratory of Genetics and Molecular Cardiology, Heart Institute (InCor), University of Sao Paulo Medical School, SP, Brazil.

BMC Medical Genetics
|January 21, 2011
PubMed

Insights

Genetic variations in CYP2C19 and ABCB1 influence clopidogrel metabolism. Ethnic differences in these gene variants affect clopidogrel-predicted metabolic phenotypes in a diverse Brazilian population.

Area of Science:

  • Pharmacogenomics
  • Clinical Pharmacology
  • Population Genetics

Background:

  • CYP2C19 and ABCB1 gene polymorphisms are crucial for personalized clopidogrel treatment.
  • Understanding allele frequencies is key to predicting drug response.

Purpose of the Study:

  • Evaluate frequencies of CYP2C19 and ABCB1 polymorphisms.
  • Identify clopidogrel-predicted metabolic phenotypes across ethnic groups in Brazil.

Main Methods:

  • Genotyping of ABCB1 c.C3435T, CYP2C19*2, CYP2C19*17, and other CYP2C19 variants.
  • Analysis included 183 Amerindians and 1,029 individuals from diverse ethnic backgrounds.
  • Polymerase chain reaction and high-resolution melting analysis were employed.

Main Results:

  • Significant inter-ethnic differences in allelic frequencies for ABCB1 c.C3435T, CYP2C19*2, and CYP2C19*17 were observed.
  • CYP2C19*3 and CYP2C19*5 alleles were not detected; CYP2C19*4 was rare (0.3%).
  • Ethnicity predicted distinct clopidogrel-predicted metabolic phenotypes in this admixed population.

Conclusions:

  • Inter-ethnic variations in ABCB1 and CYP2C19 allele frequencies exist in the Brazilian population.
  • This data aids in stratifying individuals for clopidogrel therapy personalization.
  • Findings support cost-effective programs for individualized clopidogrel treatment.
Abstract

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