abnormal metanephric mesenchyme morphology absent metanephric mesenchyme 2011-10-21T02:42:31Z MP:0011387 MPheno.ontology absence of the embryonic connective tissue made up of loosely aggregated mesenchymal cells, supported by interlaminar jelly, that gives rise to the developing metanephros; normally, interactions between the ureteric bud and the metanephric mesenchyme lead to the initiation of outgrowth and repetitive branching of the UB that ultimately generates the definitive renal collecting system and induces formation of renal vesicles from the mesenchyme tissue absent metanephric blastema absent metanephric mesoderm asbent nephric mesenchyme csmith