Higher relative CASR transcript levels may not correspond with CaSR activation and function, because mRNA CASR maturation and stability, translation, insertion of the CaSR protein into cell membrane, and CaSR turnover may be disturbed as postulated by Garner et al. [48] basing on their study on parathyroid adenomas from patients with primary hyperparathyroidism. This evidence concerns the gene CASR and primary hyperparathyroidism.