In another study on tubular proteinuria in Dent disease, Norden et al. reported a linear relationship between the albumin/creatinine ratio and the creatinine-corrected concentrations of retinol-binding protein, β2M, and alpha-1 microglobulin, all of which were around 20–30 mg/mmol creatinine (i.e., 180–270 mg/g) [18]. The gene discussed is B2M; the disease is Dent disease.