Pseudopseudohypoparathyroidism
Encyclopedia
Pseudopseudohypoparathyroidism (pseudoPHP) is an inherited disorder, named for its similarity to pseudohypoparathyroidism
in presentation. The term pseudopseudohypoparathyroidism is used to describe a condition where the individual has the phenotypic appearance of pseudohypoparathyroidism type 1a, but is biochemically normal.
It is sometimes considered a variant of Albright hereditary osteodystrophy.
It was characterized in 1952 by Fuller-Albright as "pseudo-pseudohypoparathyroidism" (with hyphen).
Hormone resistance is not present in pseudopseudohypoparathyroidism. Short stature
may be present. Obesity
is less common in pseudopseudohypoparathyroidism than in pseudohypoparathyroidism. Osteoma cutis
may be present.
Pseudopseudohypoparathyroidism and pseudohypoparathyroidism both involve the same GNAS gene, but pseudopseudohypoparathyroidism has normal calcium homeostasis because of the normal maternal allele in the kidney
.
.
Pseudohypoparathyroidism
Pseudohypoparathyroidism is a condition associated primarily with resistance to the parathyroid hormone. Patients have a low serum calcium and high phosphate, but the parathyroid hormone level is actually appropriately high...
in presentation. The term pseudopseudohypoparathyroidism is used to describe a condition where the individual has the phenotypic appearance of pseudohypoparathyroidism type 1a, but is biochemically normal.
It is sometimes considered a variant of Albright hereditary osteodystrophy.
It was characterized in 1952 by Fuller-Albright as "pseudo-pseudohypoparathyroidism" (with hyphen).
Presentation
Pseudopseudohypoparathyroidism can be best understood by comparing it to other conditions:| Condition | Appearance | PTH Parathyroid hormone Parathyroid hormone , parathormone or parathyrin, is secreted by the chief cells of the parathyroid glands as a polypeptide containing 84 amino acids... levels |
Calcium Calcium Calcium is the chemical element with the symbol Ca and atomic number 20. It has an atomic mass of 40.078 amu. Calcium is a soft gray alkaline earth metal, and is the fifth-most-abundant element by mass in the Earth's crust... |
Imprinting |
|---|---|---|---|---|
| Hypoparathyroidism Hypoparathyroidism Hypoparathyroidism is decreased function of the parathyroid glands with under production of parathyroid hormone. This can lead to low levels of calcium in the blood, often causing cramping and twitching of muscles or tetany , and several other symptoms... |
Skeletal defects | low | low | not applicable |
| Pseudohypoparathyroidism 1A | Skeletal defects | normal | low | gene defect from mother |
| Pseudopseudohypoparathyroidism | Skeletal defects | normal | normal | gene defect from father |
Hormone resistance is not present in pseudopseudohypoparathyroidism. Short stature
Short stature
Short stature refers to a height of a human being which is below expected. Shortness is a vague term without a precise definition and with significant relativity to context...
may be present. Obesity
Obesity
Obesity is a medical condition in which excess body fat has accumulated to the extent that it may have an adverse effect on health, leading to reduced life expectancy and/or increased health problems...
is less common in pseudopseudohypoparathyroidism than in pseudohypoparathyroidism. Osteoma cutis
Osteoma cutis
Osteoma cutis is a cutaneous condition characterized by the presence of bone within the skin in the absence of a preexisting or associated lesion....
may be present.
Inheritance
A mother who has inherited pseudopseudohypoparathyroidism from her father may in turn pass along pseudohypoparathyroidism 1A to her children as the imprinting pattern on the inherited paternal chomosome will be changed to the maternal pattern in the mother's ovum during meiosis.Pseudopseudohypoparathyroidism and pseudohypoparathyroidism both involve the same GNAS gene, but pseudopseudohypoparathyroidism has normal calcium homeostasis because of the normal maternal allele in the kidney
Kidney
The kidneys, organs with several functions, serve essential regulatory roles in most animals, including vertebrates and some invertebrates. They are essential in the urinary system and also serve homeostatic functions such as the regulation of electrolytes, maintenance of acid–base balance, and...
.
Linguistic significance
At 30 letters, the English name of the disorder is one of the candidates for being the longest word in EnglishLongest word in English
The identity of the longest word in English depends upon the definition of what constitutes a word in the English language, as well as how length should be compared...
.
See also
- parathyroid hormoneParathyroid hormoneParathyroid hormone , parathormone or parathyrin, is secreted by the chief cells of the parathyroid glands as a polypeptide containing 84 amino acids...
- GNAS1GNAS1GNAS complex locus, also known as GNAS, is a protein which in humans is encoded by the GNAS gene. The protein encoded by this gene is the stimulatory G-protein alpha subunit , a key component of many signal transduction pathways.- Gene :...
- Longest words in English
- Pseudopseudohypoparathyroidism on Wiktionary