Polymorphism of N-acetyltransferase 1 and correlation between genotype and phenotype in a Thai population.
OBJECTIVE
To analyze the common allele frequencies of the arylamine-N-acetyltransferase 1 (NAT1) and examine the relationship between genotype and phenotype in a Thai population.


METHODS
Peripheral blood samples from 233 Thai individuals were analyzed for genotype using polymerase chain reaction with restriction fragment-length polymorphism assays and for phenotype by determination of NAT1 enzyme kinetics in leukocytes using para-aminobenozic acid as a specific substrate.


RESULTS
Of 466 NAT1 alleles assayed, the frequency of the NAT1*4 allele (wild-type) was 0.504 (95%CI 0.458-0.551) and those of the NAT1*10, *3 and *11 alleles were 0.438 (0.392-0.484), 0.034 (0.02-0.055) and 0.024 (0.012-0.042), respectively. Neither NAT1*14A nor *14B alleles were found in this studied population. The activity of NAT1 enzyme from peripheral blood leukocytes determined in 47 subjects was found to vary widely. The intrinsic clearance and Vmax values of NAT1 enzymes with genotypes NAT1 *4/*4, *10/*10 and *4/ *10 were not significantly different.


CONCLUSIONS
The frequency distribution of the major NAT1 alleles in the Thai population has a similar pattern to some Asian populations; however, racial differences among Asian populations need further clarification.
Kukongviriyapan
Veerapol
V
Department of Pharmacology, Faculty of Medicine, Khon Kaen University, 40002, Thailand. veerapol@kku.ac.th
Prawan
Auemduan
A
Warasiha
Benjamart
B
Tassaneyakul
Wichittra
W
Aiemsa-ard
Jareerat
J
D000123:Acetyltransferases / Q000235:genetics* / Q000378:metabolism; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001191:Arylamine N-Acetyltransferase; D044466:Asian People / Q000235:genetics; D005260:Female; D005787:Gene Frequency; D005838:Genotype; D006801:Humans; D007527:Isoenzymes; D007962:Leukocytes / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D010641:Phenotype; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D013785:Thailand
D007527:Isoenzymes; D000123:Acetyltransferases; D001191:Arylamine N-Acetyltransferase; C089384:N-acetyltransferase 1