Recent studies have shown that host genetics is an important determinant of the intensity of
infection and morbidity due to human helminths. Epidemiological studies of a number of
parasite species have shown that the intensity of infection (worm burden) is a heritable
phenotype. The proportion of variance in human worm burden explained by genetic effects
varies from 0.21 to 0.44. Human genome scans have identified a locus responsible for
controlling Schistosoma mansoni infection intensity on chromosome 5q31-q33, and loci …