Pharmaceutical Research

, Volume 23, Issue 9, pp 1983–1990 | Cite as

Intra- and Inter-ethnic Differences in the Allele Frequencies of Cytochrome P450 2B6 Gene in Chinese

Short Communication



This study aimed to investigate the allele frequencies of CYP2B6 gene in 193 Han Chinese and compared with 91 Uygur Chinese. Five single nucleotide polymorphisms of CYP2B6, 64C>T, 516G>T, 777C>A, 785A>G and 1459C>T, were tested using the polymerase chain reaction–restriction fragment length polymorphism method. The allele frequencies for CYP2B6*2, CYP2B6*3, CYP2B6*4, CYP2B6*5, CYP2B6*6, CYP2B6*7 and CYP2B6*9 in Han and Uygur Chinese were 0.034 and 0.027, 0 and 0.011, 0.091 and 0.033, 0.003 and 0.049, 0.184 and 0.214, 0 and 0.022, and 0.018 and 0.044, respectively, with CYP2B6*4, CYP2B6*5, and CYP2B6*7 being significantly different between these two races (P<0.05). CYP2B6*6 was the most prevalent allele among all detected variants in Han and Uygur Chinese. The most frequent genotypes were CYP2B6*1/CYP2B6*1 (50.8%), CYP2B6*1/CYP2B6*6 (24.4%), and CYP2B6*1/CYP2B6*4 (7.3%) in Han subjects, whereas the most frequent genotypes in Uygur subjects were CYP2B6*1/CYP2B6*1 (36.3%), CYP2B6*1/CYP2B6*6 (25.3%), CYP2B6*1/CYP2B6*5 (5.5%) and CYP2B6*6/CYP2B6*6 (5.5%). The frequencies of 64C>T mutation in Han and Uygur Chinese were significantly lower than that in American Caucasian (P<0.05). These results indicate that there were marked ethnic differences in the mutant frequencies of CYP2B6 between Chinese and other ethnic groups. Further studies are warranted to explore the clinical impact of such ethnic differences.

Key words

Chinese CYP2B6 ethnicity metabolism single nucleotide polymorphism 



confidence interval


polymerase chain reaction


restriction fragment length polymorphism


single nucleotide polymorphism



The authors thank Prof. Zanger, Dr. Kathrin Klein (Dr.Margarete Fischer-Bosch Institut for Klinische Pharmakologie, Stuttgart, Germany), and Prof. Mizugaki, Dr. Masahiro Hiratsuka (Department of Clinical Pharmaceutics Tohoku Pharmaceutical University, Japan) for providing DNA reference samples. This work was supported by the National Nature Science Fund of China (No. 30572231), Guangdong Nature Science Fund (no. 2003: 36622) and the National University of Singapore Academic Research Funds (nos. R-148-000-047-101 and R-148-000-067-112).


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© Springer Science+Business Media, Inc. 2006

Authors and Affiliations

  1. 1.Institute of Clinical Pharmacology, School of Pharmaceutical SciencesSun Yat-sen UniversityGuangzhouPeople’s Republic of China
  2. 2.Department of Pharmacy, the First Affiliated HospitalSun Yat-sen UniversityGuangzhou,People’s Republic of China
  3. 3.Department of Pharmacy, Faculty of ScienceNational University of SingaporeSingaporeSingapore

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