It could be that while Vitamin D status is sufficient as per our definitions and reference ranges, but due to a polymorphism in vitamin D Receptors- VDR polymorphisms- the function of vitamin D is disrupted, abolished, or minimized, resulting in a status similar to functional vitamin D deficiency, or another polymorphism in the catabolism of vitamin D pathway leading to increased clearance of vitamin D, thereby affecting vitamin d function. This evidence concerns the gene VDR and vitamin D deficiency.