A functional polymorphism in the IL1B gene promoter, IL1B -31C&gt;T, is not associated with cerebral malaria in Thailand

Jun Ohashi,Sornchai Looareesuwan,Noppadon Tangpukdee,Izumi Naka,Jintana Patarapotikul,Hathairad Hananantachai,Katsushi Tokunaga,Akihiro Doi

doi:10.1186/1475-2875-4-38

Abstract

BackgroundIL-1β and IL-1RA levels are higher in the serum of cerebral malaria patients than in patients with mild malaria. Recently, the level of IL1B expression was reported to be influenced by a polymorphism in the promoter of IL1, IL1B -31C>T.MethodsTo examine whether polymorphisms in IL1B and IL1RA influence the susceptibility to cerebral malaria, IL1B -31C>T, IL1B 3953C>T, and IL1RA variable number of tandem repeat (VNTR) were analysed in 312 Thai patients with malaria (109 cerebral malaria and 203 mild malaria patients).ResultsIn this population, IL1B -31C>T and IL1RA VNTRwere detected, while IL1B 3953C>T (i.e., IL1B 3953T) was not observed in the polymorphism screening for 32 patients. Further analyses for IL1B -31C>T and IL1RA VNTR in 110 cerebral malaria and 206 mild malaria patients showed no significant association of these polymorphisms with cerebral malaria.ConclusionThe present results suggest that IL1B -31C>T and IL1RA VNTR polymorphisms do not play a crucial role in susceptibility or resistance to cerebral malaria.

Highlights

Interleukin 1 (IL-1) is a proinflammatory cytokine that has been suggested to play a crucial role in the pathogenesis of cerebral malaria [1]
Gyan et al [6] reported that, in Ghanaian Children, levels of parasitemia were significantly higher in uncomplicated malaria patients possessing the IL1B 3953T allele (i.e., 3953T/T and 3953C/T genotypes) than those possessing only 3953C (i.e., 3953C/C genotype), this polymorphism and the IL1RA variable number of tandem repeat (VNTR) polymorphism were not associated with cerebral malaria
The genotype and allele frequencies of the IL1B -31C>T and IL1RA VNTR polymorphisms in Thai malaria patients are shown in Tables 1 and 2

Summary

Introduction

Interleukin 1 (IL-1) is a proinflammatory cytokine that has been suggested to play a crucial role in the pathogenesis of cerebral malaria [1]. The concentration of IL-1 receptor antagonist (IL-1RA), which competes for receptor binding with IL-1, was found to be increased in Gambian children with cerebral malaria [4]. These observations raise the question of whether polymorphisms in the genes encoding IL-1β (IL1B) and IL1RA (IL1RA) are associated with cerebral malaria. Gyan et al [6] reported that, in Ghanaian Children, levels of parasitemia were significantly higher in uncomplicated malaria patients possessing the IL1B 3953T allele (i.e., 3953T/T and 3953C/T genotypes) than those possessing only 3953C (i.e., 3953C/C genotype), this polymorphism and the IL1RA variable number of tandem repeat (VNTR) polymorphism were not associated with cerebral malaria. The level of IL1B expression was reported to be influenced by a polymorphism in the promoter of IL1, IL1B -31C>T

Methods

Results

Conclusion