At 18 weeks of age, when onset of lupus-like kidney disease typically becomes evident in NZM2410 mice, 08NP and O4 + E2 mice had not developed proteinuria by albumin ELISA; unexpectedly, several O4NP mice had early levels of proteinuria, similar to unmanipulated NZM mice at that time point (data not shown). This evidence concerns the gene ALB and systemic lupus erythematosus.