Interestingly, some so-called bone-turnover markers may not be specific for indicating metabolic processes in bone tissue only, like sclerostin or bone-specific alkaline phosphatase (BSAP), but can also be expressed in cells of cardiovascular tissues [5–7], and finally these markers may in some pathological states be a marker for non-primary bone disease, like total alkaline phosphatase (AP) in liver disease and parathyroid hormone (PTH) in primary hyperparathyroidism. This evidence concerns the gene PTH and primary hyperparathyroidism.