What does PHEX do?
Normal Function. The PHEX gene provides instructions for making an enzyme that is active primarily in bones and teeth. Studies suggest that it cuts (cleaves) other proteins into smaller pieces; however, the proteins cleaved by the PHEX enzyme have not been identified.
What does PHEX stand for?
PHEX (Phosphate Regulating Endopeptidase Homolog X-Linked) is a Protein Coding gene. Diseases associated with PHEX include Hypophosphatemic Rickets, X-Linked Dominant and Hypophosphatemic Rickets, X-Linked Recessive.
What is Xlink hypophosphatemic rickets?
X-linked hypophosphatemia (XLH) is an inherited disorder characterized by low levels of phosphate in the blood. Phosphate levels are low because phosphate is abnormally processed in the kidneys, which causes a loss of phosphate in the urine (phosphate wasting) and leads to soft, weak bones (rickets).
What is Xlh disease?
X-linked hypophosphatemia or XLH (also known as familial hypophosphatemia, or, incorrectly, as Vitamin D-resistant rickets) is an extremely rare genetic disorder that causes the wasting of phosphorus, leading to problems with bone, tooth and muscle growth, development and function.
What gene causes rickets?
Causes. Hereditary hypophosphatemic rickets can result from mutations in several genes. Mutations in the PHEX gene, which are responsible for X-linked hypophosphatemic rickets, occur most frequently. Mutations in other genes cause the less common forms of the condition.
When was the PHEX gene discovered?
1995
Since a PHEX gene mutation was first identified in 1995, at least 364 mutations, including nonsense mutations, have been registered in the Human Gene Mutation Database (http://www.hgmd.cf.ac.uk/ac/index.php).
Are hybrid vehicles plug in?
Hybrid electric vehicles are powered by an internal combustion engine and one or more electric motors, which uses energy stored in batteries. A hybrid electric vehicle cannot be plugged in to charge the battery. Instead, the battery is charged through regenerative braking and by the internal combustion engine.
How common is Xlink hypophosphatemia?
A rare disorder affecting 1 in 20,000 individuals, XLH occurs when levels of the mineral phosphorus are low in the blood and phosphorus is excreted in urine. This “wasting” can cause low phosphorus levels in blood called hypophosphatemia.
What is Crysvita?
Crysvita is a medicine used for the treatment of X-linked hypophosphataemia, a hereditary disorder characterised by low levels of phosphate in the blood (hypophosphataemia).
Why is phosphate low in rickets?
The pathogenesis of hypophosphatemic rickets is clear; phosphate wasting at the proximal tubule level is the basis of the affected individual’s inability to establish normal ossification. This phenomenon is secondary to defective regulation of the sodium-phosphate cotransporter in the epithelial cell brush border.
What genetic disorders cause low phosphorus?
Table 1
| Hypophosphatemic Disorders | |
|---|---|
| Disease | Genetic mutation |
| Autosomal recessive Fanconi syndrome, hypophosphatemic rickets | NaPi2a (SLC34A1, Npt2a, NaPi-IIa) |
| Hereditary hypophosphatemic rickets with hypercalciuria | NaPi2c (SLC34A3, Npt2c, NaPi-IIc) |
| Hypophosphatemia, nephrocalcinosis and osteopenia | NHERF1 |
What is a MHEV engine?
A mild hybrid electric vehicle (MHEV) blends a traditional fuel engine and electric power. Using a smaller battery and a motor generator that can both generate electricity and help support the engine’s performance.
How does phosphorus cause rickets?
Hereditary hypophosphatemic rickets is characterized by a phosphate imbalance in the body. Among its many functions, phosphate plays a critical role in the formation and growth of bones in childhood and helps maintain bone strength in adults. Phosphate levels are controlled in large part by the kidneys.
Does Hypophosphatemia cause rickets?
Hereditary hypophosphatemic rickets is a disorder related to low levels of phosphate in the blood (hypophosphatemia). Phosphate is a mineral that is essential for the normal formation of bones and teeth. In most cases, the signs and symptoms of hereditary hypophosphatemic rickets begin in early childhood.
What type of drug is Crysvita?
Crysvita belongs to a class of drugs called Monoclonal Antibodies, Endocrine. It is not known if Crysvita is safe and effective in children younger than 1 year of age.
Why is alkaline phosphatase high in rickets?
Bone specific alkaline phosphatase isoenzyme is elevated as a result of increased osteoblastic activity. The highest total ALP values have been attributed to an increased bone isoenzyme level due to Paget disease or rickets/osteomalasia.
What is the function of the X-linked hypophosphatemic rickets gene?
The protein encoded by this gene is a transmembrane endopeptidase that belongs to the type II integral membrane zinc-dependent endopeptidase family. The protein is thought to be involved in bone and dentin mineralization and renal phosphate reabsorption. Mutations in this gene cause X-linked hypophosphatemic rickets.
Is there a role for phosphate in fgf23-related hypophosphatemia?
X-Linked Hypophosphatemia and FGF23-Related Hypophosphatemic Diseases: Prospect for New Treatment Phosphate plays essential roles in many biological processes, and the serum phosphate level is tightly controlled.
What is the pathophysiology of X-linked hyperplasia (XLH)?
Moreover, a novel molecular signaling pathway was identified for the pathogenesis of XLH, which consists of a PHEX mutation, upregulation of FGF23, and inhibition of p38 MAPK activation.