Urine protein levels were analyzed to determine glomerular disease onset at different time points (Figure 2a,b), and progressive proteinuria was detected in Epb41l5fl/fl*Nphs1-rtTA-3G*tetOCre knockout mice, with an onset of albuminuria at 3–4 weeks p. i. KO animals showed severe hypoalbuminemia, detected by analysis of serum albumin levels already 8 weeks p. i. (Figure 2c). Here, NPHS1 is linked to Hypoalbuminemia.