A study on 55 young adults who had participated as newborns in a prospective cohort study showed inverse correlations of umbilical cord Pb concentration and expression of potential AD biomarkers e.g., ADAM9, RTN4, and LRPAP1 genes, hence demonstrating that early-life Pb exposure influences biological processes involved in AD pathogenesis (20). Here, RTN4 is linked to Alzheimer disease.