SCIENTIFIC BACKGROUND

AP2S1CASRGNA11
Category:

Hypocalciuric hypercalcemia (FHH) is a disorder of calcium balance that is characterized by elevated blood calcium levels and decreased urinary calcium excretion. The familial form is inherited in an autosomal dominant manner and is usually caused by inactivating variants in the CASR gene (familial hypocalciuric hypercalcemia type 1, FHH1). The calcium-sensitive receptor CaSR plays an important role in regulating extracellular calcium homeostasis. The signal transduction pathway of CaSR involves the α-11 G protein (Gα11) subunit and the adapter-related protein complex 2σ (AP2σ) subunit. These are encoded by the GNA11 and AP2S1 genes, respectively. CaSR can detect small changes in extracellular Ca2+ and maintains calcium homeostasis in the body by regulating the synthesis and secretion of PTH and urinary calcium reabsorption.

 

Approximately 65% of all cases are accounted for by FHH type 1. In a smaller number of cases, alterations are detected in the GNA11 gene (FHH2) and the AP2S1 gene (FHH3). FHH is usually asymptomatic, but rarely symptoms such as fatigue, weakness, excessive thirst and concentration problems occur. Recurrent pancreatitis, chondrocalcinosis, and premature vascular calcification have been described in isolated cases.

 

Typically, this form of calcium balance disorder does not require distinct treatment. However, it's important to distinguish FHH from other forms of hypercalcemia that require treatment, such as primary hyperparathyroidism, which is seen in syndromes like MEN1 and MEN2, and can be addressed surgically.

 

References

Marini et al. 2017, Clin Cases Miner Bone Metab 14:60 / Wasserman et al. 2017, Clin Cancer Res 23:e123 / Thakker et al. 2016, J Intern Med 280:574

GENES

AP2S1CASRGNA11

ASSOCIATED TESTS

How to order

LATEST ARTICLES

Antimicrobial resistance (AMR) is one of the most pressing global health threats, and accurate identification and surveillance of multidrug-resistant...

Read more

Colorectal cancer remains a significant health concern globally. While genetic factors play a crucial role in its development, identifying the exact ...

Read more

A new meta-analysis links trans-kingdom gut microbiota (bacteria, eukaryotes, viruses, archaea) to immune checkpoint inhibitor (ICI) response in canc...

Read more

Reproductive health is a fundamental aspect of human well-being, affecting individuals and communities worldwide [1]. It encompasses a wide range of ...

Read more

It seems as though everyone is talking about artificial intelligence, usually referred to as AI, these days! Indeed, not only are AI tools now access...

Read more

Orphan drugs are those developed specifically for the treatment of rare diseases. Within the pharmaceutical industry, the drug development process is...

Read more

A study of 629 pregnancies with ultrasound-detected anomalies found that exome sequencing identified pathogenic variants in 14% of cases. The detecti...

Read more

Breast cancer is a type of cancer that originates in the breast cells. Genetic changes in the DNA of the healthy breast cells can lead to the formati...

Read more

Cardiovascular diseases affect the heart and blood vessels and are a leading cause of illness and death. Some are hereditary, and genetic testing can...

Read more

A recent study tracked molecular changes in 108 people over time, revealing that aging involves critical shifts around ages 44 and 60. These changes ...

Read more