CASE REPORT A novel CaSR mutation pr h

somal dominant disorder characterized by modestly ele-vated serum calcium (Ca), inappropriately high CaSR is located on chromosome 3q13.3–21 and encodes for a 1078 amino acid sequence. Normally, elevated Tonyushkina et al. International Journal of Pediatric Endocrinology 2012, 2012:13 http://www.ijpeonline.com/content/2012/1/13from totally asymptomatic to fatal. In the neonatalChestnut St. Dept of Pediatrics, Springfield, MA 01199, USA Full list of author information is available at the end of the articleparathyroid hormone (PTH) levels and low urinary Ca excretion [1]. FHH is caused by inactivating mutations of the gene encoding the Calcium-Sensing Receptor (CaSR), a seven transmembrane G-protein-coupled re-ceptor. The CaSR is expressed primarily in parathyroid chief cells and renal tubular cells and activates an levels of serum calcium activate the CaSR which then inhibits both the secretion of PTH in the parathyroid glands and the reabsorption of Ca2+ and Mg2+ in th