Correlation Between Phenotype And Genotype Of The Human Polymorphism N-acetyltransferase 1 And Substrate Regulation Of Phenotype

Background Arylamine N-acetyltransferase-1 (NAT1) is a polymorphically expressed enzyme that is widely distributed throughout the body. NAT1 genotype and phenotype is known to be variable in human populations. Therapeutic agents that are substrates for these isoenzymes (including p-aminobenzoic acid, 5-aminosalicyclic acid) have been used to evaluate the role of the N-acetylation polymorphisms of NAT1 in the treatment of disease among individuals of differing acetylator phenotypes.Objective To establish the method of detecting the NAT1 genotype, and investigate its distribution of polymorphism, and analyze the correlation between the genotype and the phenotype in a Chinese Hans population. Meanwhile, the regulation of NAT1 activity and its mRNA transcription level by para-aminobenzoic acid (PABA) were researched. Methods The peripheral blood samples from 140 Han people were collected and analyzed for NAT1 genotypes by multiple PCR and PCR-RFLP method, the NAT1 enzyme kinetics in leukocytes were determinated for NAT1 phenotype by HPLC, and para-aminobenozic acid as a specific substrate. Human peripheral blood lymphocytic cells were cultured in medium supplemented with different dosage PABA(2, 6, 18uM) for 24h, 48h and 72h, the NAT1 activity and its mRNA transcription level by PABA were investigated by HPLC and reverse transcription PCR(RT-PCR) method respectively. Results the NAT1 genotype of Chinese Hans population were distinguished accurately by multiple PCR and PCR-RFLP method, and were not interfered by the interaction of several restriction endonucleases. The allelic frequencies of NAT1*3, NAT1*4. NAT1*10 and NAT1*11...