In a recent systematic review and meta-analysis of 128 RCTs (312), Yeung et al concluded that the administration of vitamin D in patients with stage 3, 4, and 5 CKD and CKD-MBD lowers serum PTH and ALP; however, it increases serum calcium levels and moreover, the results regarding the effects on fracture risk are uncertain. This evidence concerns the gene PTH and Marchiafava-Bignami disease.