Kurt A, et al. - Researchers assessed if YKL-40 (chitinase 3-like 1 protein) played a role in pterygium pathogenesis. Findings suggested a possibility of YKL-40 to play a significant role in pterygium pathogenesis. In the epithelial, endothelial, and stromal cells of the pterygium tissues, statistically significantly higher YKL-40 expression was seen vs the control tissues. Pterygium subgroups and YKL-40 expression did not demonstrate a significant correlation.