Ethnic differences of two non-synonymous single nucleotide polymorphisms in CDA gene.
Emiko Sugiyama1, Su-Jun Lee, Sang Seop Lee
1Project Team for Pharmacogenetics, National Institute of Health Sciences, Tokyo 158-8501, Japan.
Drug Metabolism and Pharmacokinetics
|January 5, 2010
Summary
This study investigated genetic variations in the cytidine deaminase (CDA) gene across diverse ethnic groups. Findings reveal significant ethnic differences in the minor allele frequencies of key CDA polymorphisms, impacting drug metabolism.
Area of Science:
- Pharmacogenetics
- Human Genetics
- Drug Metabolism
Background:
- Cytidine deaminase (CDA), an enzyme crucial for metabolizing anticancer drugs like gemcitabine and ara-C, exhibits genetic variations.
- Two significant CDA polymorphisms, 79A>C (Lys27Gln) and 208G>A (Ala70Thr), have known minor allele frequencies (MAFs) in specific populations.
- Understanding ethnic variations in CDA MAFs is essential for personalized cancer therapy and pharmacogenetic studies.
Purpose of the Study:
- To determine and compare the MAFs of CDA polymorphisms 79A>C and 208G>A in Korean, Japanese, Chinese-American, Caucasian-American, and African-American healthy volunteers.
- To identify potential ethnic differences in the distribution of these CDA genetic variants.
- To provide foundational data for pharmacogenetic research involving CDA-metabolized drugs.
Main Methods:
- Genotyping was performed on DNA samples from 200 Korean, 206 Japanese, 200 Chinese-American, 150 Caucasian-American, and 150 African-American healthy volunteers.
- Minor allele frequencies (MAFs) for the 79A>C (Lys27Gln) and 208G>A (Ala70Thr) CDA polymorphisms were calculated for each ethnic group.
- Statistical analysis was used to compare MAFs across the studied populations.
Main Results:
- The MAF for 79A>C (Lys27Gln) varied significantly, with the highest observed in Caucasian-Americans (0.327) and the lowest in African-Americans (0.087).
- The MAF for 208G>A (Ala70Thr) was low across all groups, detected in Koreans (0.005) and Japanese (0.022), but absent in Chinese-Americans, Caucasian-Americans, and African-Americans.
- The MAF of 208G>A appears higher in Japanese and possibly Korean populations compared to Chinese-Americans.
Conclusions:
- Significant ethnic variations exist in the MAFs of CDA polymorphisms 79A>C and 208G>A.
- These findings highlight the importance of considering ethnic background in pharmacogenetic studies of cytidine deaminase.
- The generated data provide crucial insights for optimizing the use of CDA-metabolized anticancer drugs in diverse patient populations.
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