A recent study followed prospectively 94,665 individuals from the Danish general population for up to 23 years and analyzed for plasma CHI3L1 levels (n = 21,584) and CHI3L1 rs4950928 genotype (n = 94,184), and reveals that baseline elevated plasma CHI3L1 is not a cause, but a strong marker of increased risk of future infectious diseases in individuals in the general population.153 The roles of CHI3L1 are further summarized according to the organ systems of the human body in Table 3. This evidence concerns the gene CHI3L1 and infectious disease.