For instance, in wild wood mice, total fecal IgA was negatively associated with Heligmosomoides polygyrus and Eimeria infection load, suggesting a protective effect, whereas parasite‐specific IgG1 concentration was positively associated with H. polygyrus infection load and negatively associated with pinworm infection load (Clerc et al., 2018), suggesting that IgG1 reflects parasite exposure to H. polygyrus and has protective effects through cross‐reactivity to pinworms. The gene discussed is CD79A; the disease is enterobiasis.