title: Alleles -308A and -1031C in the TNF-alpha gene promoter do not increase the risk but associated with circulating levels of TNF-alpha and clinical features of vivax malaria in Indian patients.
abstract: The biological significance of TNF promoter polymorphism and infectious disease association prompted us to investigate whether TNF-alpha -308 G/A and -1031 T/C promoter polymorphisms are associated with Plasmodium vivax infection, cellular TNF-alpha level and possibly with clinical symptoms by employing PCR-RFLP methods. An overall significant elevation of serum TNF-alpha, IL-6 content (p=0.0002, p=0.002, respectively), whereas highly significant depletion of IL-10 content (p=0.0001) was observed in vivax patients. In addition, TNF-alpha concentration in patients with and without fever were found to be significant (p=0.0001, p=0.0004, respectively). The genotypic distribution for -308 G/A and -1031 T/C positions were found non significant, but it was clinically potent to observe statistically significant distribution of genotypes (p=0.032) in patients with and without fever. Furthermore, the TNF-alpha level in TNF1 and TNF2 genotype for -308 position was significantly higher (p=0.010, p=0.006 respectively). In case of -1031 position TNF-alpha level was significant in ancestral (TT) genotype (p=0.0007) in patients compared to healthy subjects and significantly higher in rare (CC) genotype (p=0.021) as compared to ancestral genotype. In addition, the two polymorphisms 308G/A and -1031T/C were in highly significant LD (D'=0.7992, r(2)=0.6005, p=0.0001) in the patients as well as it is interesting to report that the distribution of novel 308A: 1031C alleles associated haplotypes are nearly the same in patients (0.2610) and in healthy subjects (0.2636). In view of present observation of promoter polymorphism with TNF-alpha level and other clinical parameters of vivax infection, we suggest that evaluation of TNF level and its polymorphisms in the promoter region may be considered to be reliable molecular and immunological markers, possess promising rational for diagnostic potential and immunotherapeutic interventions in clinical vivax malaria. Genetic variation in the promoter region is of biological significance and may play important roles in host defense mechanisms against vivax infection by enhancing cell-mediated immunity and stimulating the protective immunological cascade.
authors.affiliation: Biochemistry & Molecular Biology, 2-Nanak Enclave Campus, Near Radio Colony, National Institute of Malaria Research, Delhi 110009, India.
authors.forename: Mohd
authors.initials: M
authors.lastname: Sohail
authors.forename: Asha
authors.initials: A
authors.lastname: Kaul
authors.forename: Prerna
authors.initials: P
authors.lastname: Bali
authors.forename: M
authors.initials: M
authors.lastname: Raziuddin
authors.forename: M P
authors.initials: MP
authors.lastname: Singh
authors.forename: O P
authors.initials: OP
authors.lastname: Singh
authors.forename: A P
authors.initials: AP
authors.lastname: Dash
authors.forename: T
authors.initials: T
authors.lastname: Adak
mesh_terms: D000328:Adult; D000483:Alleles; D005260:Female; D005787:Gene Frequency; D006801:Humans; D007194:India; D016780:Malaria, Vivax / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D008297:Male; D011110:Polymorphism, Genetic; D011401:Promoter Regions, Genetic; D012306:Risk; D014409:Tumor Necrosis Factor-alpha / Q000097:blood / Q000235:genetics* / Q000276:immunology
chemical_list: D014409:Tumor Necrosis Factor-alpha