CHIA and ascariasis: In a search for genetic variants supporting the IgE hyperresponsiveness of ascariasis, we found that SNPs of the genes coding for acidic mammalian chitinase (CHIA) and chitinase 3 like 1 (CHI3L1) were significantly enriched in high IgE responders to the resistance marker ABA-1; in addition, SNPs in the tumor necrosis factor superfamily member 13b gene (TNFSF13B) encoding the cytokine B cell activating factor were associated with high levels of total IgE [18].