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Primary open-angle glaucoma is more prevalent among black Americans of African ancestry (AAs) than in Americans of white ancestry (CAs). To investigate the possibility that this difference may reflect differences in the extracellular matrix component elastin, Urban et al. (876) compared several biomarkers related to elastin biosynthesis and cross linking in optic nerve head (ONH) tissues and astrocyte cultures from normal AA and CA donor eyes. They found no consistent difference in the distribution of elastin in ONH tissue sections. However, they did find evidence of decreased elastin cross linking in AA ONH tissue. In AA ONH astrocyte cultures, they found reduced mRNA for elastin and for LOXL2 (a type of lysyl oxidase present at the ONH) as well as a difference in elastin gene splicing that may inhibit cross link formation. They propose that reduced elastin cross linking in AA ONH tissue may contribute to population-specific risk for POAG and that elastin and LOXL2 may be candidate susceptibility genes for POAG. The major strength of this study is the large number of well-done complementary analyses addressing many different aspects of elastin biosynthesis and crosslink formation. A detailed description of the racial background of each of the donor eyes would have been useful, if available. As only normal eyes from each racial group were studied, the relevance to glaucoma needs to be studied. It remains possible there are important differences in elastin biology that are rare in normal AA eyes but common in AA eyes that develop glaucoma. Thus, this work represents an important first step that justifies further studies comparing elastin biology within glaucomatous AA and CA eyes.