Analysis of the correlation relationship between vitamin D concentration and biochemical parameters characterizing phosphorus-calcium metabolism and the level of parathyroid hormone showed that in CeD, an inverse correlation was found between vitamin D content and the level of alkaline phosphatase (respectively r = −0.710 and r = −0.623, r = −0.589) and parathyroid hormone (respectively r = −0.610 and r = −0.659, r = −0.623) (Table 5). This evidence concerns the gene PTH and cranioectodermal dysplasia.