N-acetyltransferase polymorphism in patients with Behcet's disease

Objectives: The objective of our study was to investigate the possible role of human arylamine N-acetyltransferase 2 (NAT2) polymorphism in susceptibility to Behcet's disease.Methods: Eighty-five patients with Behcet's disease gave their written informed consent to participate in the study. Seven point mutations (G191A, C282T, T341C, C481T, A803G, G590A, G857A) in the NAT2 gene were analysed using polymerase chain reaction/restriction fragment length polymorphism techniques. In addition, each patient received 100 mg dapsone orally to determine their NAT2 phenotype. Dapsone and its metabolite monoacetyl-dapsone were measured in 3-h plasma samples using high-performance liquid chromatography. Subjects with an acetylation ratio (monoacetyl-dapsone/dapsone) less than 0.4 were defined as slow acetylators.Results: Of 85 patients with Behcet's disease, 54 (63.5%) were identified as genotypically slow acetylators. However, 60% (51 of 85) of patients were diagnosed as slow acetylators according to mono acetyl-dapsone/dapsone ratio. Thus, a low incidence of genotype/phenotype discrepancy (3.5%) was observed in Turkish patients with Behcet's disease. When we compared our results with previous phenotyping and genotyping studies in the Turkish population, frequencies of slow and rapid acetylators were not statistically different in patients with Behcet's disease. The frequency of the *5B allele was found to be slightly higher in patients with Behcet's disease than historic controls (44.7 vs 35.6%, P=0.039). However, there was no significant difference in the frequency of the overall genotypes and alleles of NAT2 between patients and controls.Conclusion: Although the frequency of the NAT2*5B allele, responsible for slow acetylation, was slightly higher in patients than historic controls, our results failed to show an association between NAT2-acetylator status and risk for developing Behget's disease

N-acetyltransferase polymorphism in patients with Behcet's disease

Objectives: The objective of our study was to investigate the possible role of human arylamine N-acetyltransferase 2 (NAT2) polymorphism in susceptibility to Behcet's disease

Cyp2C19 Genotype Does Not Represent A Genetic Predisposition In Idiopathic Systemic Lupus Erythematosus

Background-The aetiology of systemic lupus erythematosus (SLE) is still unknown. In several cases, however, chemicals or drugs were identified as aetiological agents and associations with certain phenotypes of drug metabolising enzymes have been reported. The purpose of this study was to discover if there is an association between CYP2C19 polymorphism and susceptibility to SLE. Methods-Racemic mephenytoin (100 mg orally) was given to healthy volunteers (n=161) and SLE patients (n=37) and then S-mephenytoin and R-mephenytoin were determined in eight hour urine samples. A 10 ml blood sample was obtained from healthy volunteers (n=80) and SLE patients (n=69) for genotypic assay. Each blood sample was tested for the detection of CYP2C19*1 and CYP2C19*2 (formerly wt and mi respectively) by oligonucleotide ligation assay. Results-The ratio of SIR-mephenytoin ranged from <0.1 to 1.293 in healthy subjects and from <0.1 to 1.067 in SLE patients. FM phenotype was observed in 2 of 37 patients with idiopathic SLE (5.4 %) and 6 of 161 healthy subjects (3.7 %). There were no significant differences in the frequency of PM phenotypes between the groups (Fisher's exact test, p= 0.64) or in the frequency distribution profiles of ratios of S-mephenytoin to R-mephenytoin. No significant differences in distribution of overall genotypes and in allele frequencies were observed between the two groups. No significant relation was found between clinical features and the overall genotype. Conclusion-The results of this study indicate that CYP2C19 genotype does not represent a genetic predisposition in idiopathic SLE patients.WoSScopu

N-acetyltransferase polymorphism in patients with Behcet's disease

Objectives: The objective of our study was to investigate the possible role of human arylamine N-acetyltransferase 2 (NAT2) polymorphism in susceptibility to Behcet's disease.Methods: Eighty-five patients with Behcet's disease gave their written informed consent to participate in the study. Seven point mutations (G191A, C282T, T341C, C481T, A803G, G590A, G857A) in the NAT2 gene were analysed using polymerase chain reaction/restriction fragment length polymorphism techniques. In addition, each patient received 100 mg dapsone orally to determine their NAT2 phenotype. Dapsone and its metabolite monoacetyl-dapsone were measured in 3-h plasma samples using high-performance liquid chromatography. Subjects with an acetylation ratio (monoacetyl-dapsone/dapsone) less than 0.4 were defined as slow acetylators.Results: Of 85 patients with Behcet's disease, 54 (63.5%) were identified as genotypically slow acetylators. However, 60% (51 of 85) of patients were diagnosed as slow acetylators according to mono acetyl-dapsone/dapsone ratio. Thus, a low incidence of genotype/phenotype discrepancy (3.5%) was observed in Turkish patients with Behcet's disease. When we compared our results with previous phenotyping and genotyping studies in the Turkish population, frequencies of slow and rapid acetylators were not statistically different in patients with Behcet's disease. The frequency of the *5B allele was found to be slightly higher in patients with Behcet's disease than historic controls (44.7 vs 35.6%, P=0.039). However, there was no significant difference in the frequency of the overall genotypes and alleles of NAT2 between patients and controls.Conclusion: Although the frequency of the NAT2*5B allele, responsible for slow acetylation, was slightly higher in patients than historic controls, our results failed to show an association between NAT2-acetylator status and risk for developing Behget's disease