Also, histological analysis of fetal and adult kidneys did not reveal any morphological differences (Fig. 4M–R), another phenotypic trait of Fraser syndrome, although the mutants lacked Hmcn1 normally present at the BM of renal epithelia and in the ECM around nephron progenitor cells and in renal stroma (Fig. 4S, T). The gene discussed is HMCN1; the disease is Fraser syndrome.