Genome-Wide Association Study of Serum YKL-40 Levels. Homo sapiens

The chitinase-like protein, YKL-40, is involved in inflammation and tissue remodeling. Serum YKL-40 levels were elevated in patients with asthma and correlated with severity, thickening of the subepithelial basement membrane, and pulmonary function in previous studies. We conducted a genome-wide association study of serum YKL-40 levels in 632 individuals from a founder population of European descent, the Hutterites. The most significant associations were with a group of single nucleotide polymorphisms (SNPs) that were in perfect linkage disequilibrium (LD) in CHI3L1, the gene encoding YKL-40 (P<1.1x10-12). This association was present in children studied at birth (P=0.001) and at years 1 (P=0.009), 3 (0.0002), and 5 (P=0.002). Moreover, these SNPs were associated with asthma (P=0.047), bronchial hyperresponsiveness (P=0.0019), and measures of pulmonary function (P = 0.046 to 0.0020) in the Hutterites. A SNP in this LD group predicted asthma... (for more see dbGaP study page.)