Haplotypes of IL12B promoter polymorphisms condition susceptibility to severe malaria and functional changes in cytokine levels in Thai adults

Abstract

Polymorphic variability in immune response genes, such as IL12B, encoding the IL-12p40 subunit is associated with susceptibility to severe malaria in African populations. Since the role of genetic variation in conditioning severe malaria in Thai adults is largely unexplored, the functional association between IL12B polymorphisms [ie, IL12Bpro (rs17860508), and IL12B 3'UTR T/G (rs3212227)], severe malaria, and cytokine production was examined in patients with Plasmodium falciparum infections (n= 355) recruited from malaria endemic areas along the Thai-Myanmar border in northwest Thailand. Circulating IL-12p40 (p= 0.049) and IFN-γ (p= 0.051) were elevated in patients with severe malaria, while only IL- 12p40 was significantly higher in severe malaria patients with hyperparasitaemia (p= 0.046). Carriage of the IL12Bpro1. 1 genotype was associated with enhanced severity of malaria …