%A Vanderborght PR
%A Matos HJ
%A Salles AM
%A Vasconcellos SE
%A Silva-Filho VF
%A Huizinga TWJ


%T Single nucleotide polymorphisms (SNPs) at -238 and -308 positions in the TNFα promoter: clinical and bacteriological evaluation in leprosy

%0 Journal Article

%D 2004

%J International Journal of Leprosy and other Mycobacterial Diseases

%P 0148-916X

%V 72

%N 2

%X Tumor necrosis factor alpha (TNFα)  plays a key role in orchestrating the complex events involved in inflammation and immune response. The presence  of single nucleotide polymorphisms (SNPs) within the promoter region of the  TNFa gene has been associated with a number of diseases. The aim of this study  was to investigate the distribution of polymorphisms at positions -238 (G/A)  and -308 (G/A) at the TNFα  promoter, and its association to the outcome of different clinical forms of  leprosy. Furthermore, the bacteriological index (BI) was evaluated among  genotyped multibacillary (MB) patients in order to investigate the possible influence of each polymorphism on the  bacterial load. This study included a total of 631 leprosy patients being 401  MB and 230 paucibacillary (PB), that was further separated according to its  ethnicity (Afro- and Euro-Brazilians). The combination of SNPs in haplotypes  generated three different arrangements: TNFG-G, TNFG-A and TNFA-G. In spite of  the marked differences observed in the frequency of the haplotypes along the  ethnic groups, no statistical differences were observed in haplotype frequencies  between MB and PB patients. The BI analyses showed a lower bacteriological  index among the -308 carriers, while the BI of the -238 carriers was higher.  Although no significance has been achieved  in this analysis regarding the influence  of the polymorphisms to the development of the clinical outcome, it seems that  in a different stage (among the MB patients) the polymorphisms could contribute  to the degree of severity observed.