Furthermore, the functional CHI3LI promotor SNP −131C→G (rs4950928) increases the mRNA transcript levels coding for the YKL-40 protein in a genome wide study of gene expression in Epstein-Barr virus-transformed lymphoblastoid cells from children with asthma [10] and is shown to be predictive of asthma, bronchial hyperresponsiveness and reduced lung function [11]. Here, CHI3L1 is linked to asthma.