Increased genotype frequency of N-acetyltransferase 2 slow acetylation in patients with rheumatoid arthritis.

OBJECTIVES

Acetylation polymorphism can alter therapeutic responses and toxicity to certain xenobiotics and may also be a factor that influences a patient's susceptibility to certain diseases. We investigated whether patients with rheumatoid arthritis (RA) differed from healthy individuals with regard to genotype of the polymorphic enzyme N-acetyltransferase 2 (NAT2).

METHODS

NAT2 polymorphism was compared in 118 healthy subjects and 82 patients with RA. NAT2 alleles (*4, *5, *6, and *7) were determined by polymerase chain reaction-restriction fragment length polymorphism methods with deoxyribonucleic acid extracted from peripheral blood.

RESULTS

A statistically significant increase in the proportion of homozygous slow acetylators with 2 mutated alleles (84.1%) was found among patients with RA in comparison with healthy subjects (52.5%; P <.0001). The risk of development of RA was almost 5-fold greater in slow acetylators than in fast acetylators (odds ratio, 4.79; 95% confidence interval, 2.28-10.21). There was no correlation between NAT2 polymorphism and presence of rheumatoid factor, extra-articular manifestations, and age at first occurrence of disease symptoms.

CONCLUSIONS

NAT2 slow acetylation genotype may be a risk factor of individual susceptibility to RA.