Transcriptomic analysis of kidney biopsies has demonstrated the potential to improve diagnosis of graft rejection. Molecular assessment of kidney graft rejection based on the Banff Human Organ Transplant consensus gene panel is an available and validated tool (HistoMx). However the applicability of molecular assessment of graft biopsy in real life setting is unclear. The main objective is to assess the clinical need of molecular assessment of kidney graft biopsy for diagnosis in real world clinical practice. The secondary objectives are to measure : clinical outcomes at 12-months follow up including patient survival, graft function and graft survival, diagnosis of graft rejection after integrating molecular assessment to standard histology, biology and immunology, and to evaluate therapeutic changes and impact on clinical outcome.