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Published on: March 28, 2017
Genotype and allele frequency of CYP2D6 in Tamilian population
C Adithan1, N Gerard, A T Naveen
1Pharmacogenomics Laboratory, Department of Pharmacology, Jawaharlal Institute of Post-graduate Medical Education and Research, 605006 Pondicherry, India. adithan@vsnl.com
Objective:
To assess the frequency of CYP2D6 *3, *4, *5 and *10 allelic variants in a South Indian population and compare the frequencies with other major populations.
Methods:
Polymerase chain reaction (PCR) or PCR-restriction fragment length polymorphism (RFLP)-based methods were used to identify the CYP2D6 genotypes of 106 healthy unrelated male and female volunteers of Tamilian origin. The allele and genotype frequencies observed were compared with other major populations.
Results:
The *10 allele was the most frequent mutant allele in Tamilians (20.3%). The *5 allele occurred at 0.9% and the *3 allele was not detected. The most frequent allele causing enzyme inactivation was *4 allele in Tamilians (6.6%), which is significantly higher than that reported in Japanese (0%).
Conclusions:
The *10 allele is the most common mutant allele in Tamilians. The CYP2D6*4 and CYP2D6*5 alleles are distributed in a significantly different way in the Tamil population relative to Oriental populations.
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