Association of CD40L gene polymorphism with severe Plasmodium falciparum malaria in Indian population

Background & objectives: Many host genetic factors are associated with the disease severity and fatal outcome of falciparum malaria. CD40L gene has been found to be one of the most important factors associated with malaria in African countries. This study was aimed to investigate the possible association of CD40L gene polymorphism in severe falciparum malaria in Indian adults. Methods: One hundred fifteen adult cases with severe falciparum malaria were included in the study. Two single-nucleotide polymorphisms (SNPs) of CD40L gene, CD40L-726(C/T) and CD40L+220(C/T) were investigated, and the possible association with different clinical sub-phenotypes of severe falciparum malaria were analyzed. Results: Statistically no significant difference was observed in the incidence of CD40L-726C between the patients and control group. The incidence of CD40L+220C allele was found to be significantly higher (OR, 2.25; p = 0.03) in male patients compared to controls but no significant difference was observed in females. Haplotype data showed the susceptibility of -726T/+220C haplotype to severe malaria whereas -726C/+220T was associated with protection against severe malaria. CD40L+220C allele was associated with severe malarial anaemia in males (chi(2) = 6.60; p = 0.01). Interpretation & conclusion: CD40L gene polymorphism was found to be associated with severe falciparum malaria in Indian population especially in severe malarial anaemia. CD40L may be considered as a factor of immunity in understanding the pathophysiology of falciparum malaria.