Working… Menu

Pharmacogenetics Study in Taiwan's Ethnic Groups

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT00459251
Recruitment Status : Completed
First Posted : April 11, 2007
Last Update Posted : April 11, 2007
Department of Health
Information provided by:
Mackay Memorial Hospital

Brief Summary:
This main purpose of this study is to understand the difference and distribution of drug-metabolizing enzyme genetic polymorphisms among Taiwan ethnicities. The subjects of study include Atayal, Pawlan, Yami, Tsou, Ami, Minnan and Hakka. We anticipate establishing a reference for the clinical medication in various ethnic groups according to the difference and distribution of the genetic polymorphisms.

Condition or disease

Detailed Description:

It has been shown that the same medication causes different responses in different individuals. In addition to environments, diets, and physical conditions, the genetic variations play an important role in the various responses. For instant, genetic variations in drug-metabolism enzymes may be responsible to different abilities in drug metabolism. Some people have higher drug-metabolizing enzyme activity for certain drug and may need higher dose to reach the effective therapy; some are poor in metabolizing the same drug, and may cause adverse drug reactions. Genetic variation also may cause different functions of the cell transporters. The most notable example is that some tumor cells have a kind of transporters called p-glycoprotein which can pump out the anti-tumor drugs to extracellular, and it turns the tumor cells become resistant to the drugs. Hence, if we can elucidate the gene variation of each individual, we can give each individual different therapy based on their genetic variations. This approach is called 「individualized medicine」.

In order to reach the goal of individualized medicine, many studies have been focused on drug-metabolizing enzyme genetic variations between races or ethnicities. Especially, single nucleotide polymorphism provides a very important basis to clinical medication. N- acetyltransferase 2 (NAT2) is one kind of drug-metabolizing enzymes and its single nucleotide polymorphisms have remarkable effect on drug-metabolism. Only 10~30 % are slow acetylators in Asian population, but 40~70% are found in Caucasian population. Cytochrome P450 (CYP450,CYP) is another important drug-metabolizing enzyme family. Among the family, the CYP2C9, CYP2C19, and CYP2D6 play key roles on drug metabolism. Many literatures showed that all the three enzymes have various distributions of SNPs in different races. It indicates that different races may have different abilities in drug-metabolizing enzymes. Therefore, it is important to provide a strategy to overcome the difficulties in individualized medicine.

In the previous studies, scientists often take Chinese as the representatives of Asian people and the Minnan/ Hakka or so-called Han people as the subjects when study the Taiwan ethnicity. The genetic variations in the Taiwan aborigines are poorly investigated. It has been showed that remarkable genetic variations in human leukocyte antigen (HLA) between Taiwan aborigines and Minnan/ Hakka by Lin ML and her colleagues. They are highly homogenous within each tribe, but diversified among the different tribes due to long-term isolation. Therefore, we expect to establish a database of genetic variations in drug-metabolism enzymes among these groups in order to use as the basis for clinical medication. This study includes seven groups, and each of them has 50 independent samples for drug-metabolizing enzyme genetic polymorphism analysis. The important enzymes, CYP2C9, CYP2C19, CYP2D6 and NAT2, etc., are studied in this project. ABI 7900HT instrument and traditional polymerase chain reaction (PCR) - restriction fragment length polymorphism (RFLP) both are used for SNPs analysis, and gene sequence also would be used to confirm the results.

Layout table for study information
Study Type : Observational
Enrollment : 350 participants
Observational Model: Defined Population
Primary Purpose: Screening
Time Perspective: Cross-Sectional
Time Perspective: Retrospective
Official Title: The Pharmacogenetics Study of Drug-Metabolising Enzyme Genetic Polymorphisms in Aboriginal and Minnan/Hakka Ethnic Groups in Taiwan
Study Start Date : December 2006
Actual Study Completion Date : April 2007

Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.

Layout table for eligibility information
Ages Eligible for Study:   Child, Adult, Older Adult
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  • This study includes seven groups, and each of them has 50 independent samples for drug-metabolizing enzyme genetic polymorphism analysis.

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT00459251

Layout table for location information
Mackay Memorial Hospital
Taipei, Taiwan, 100
Sponsors and Collaborators
Mackay Memorial Hospital
Department of Health
Layout table for investigator information
Principal Investigator: Li-Jiuan Shen, Ph.D. School of Pharmacy, National Taiwan University

Layout table for additonal information Identifier: NCT00459251     History of Changes
Other Study ID Numbers: MMH-I-S-304
First Posted: April 11, 2007    Key Record Dates
Last Update Posted: April 11, 2007
Last Verified: April 2007
Keywords provided by Mackay Memorial Hospital: