Primordial Dwarfism
Encyclopedia
Primordial dwarfism is a form of dwarfism
that results in a smaller body size in all stages of life beginning from before birth
. More specifically, primordial
dwarfism is a diagnostic category including specific types of profoundly proportionate dwarfism, in which individuals are extremely small for their age, even as a fetus. Most individuals with primordial dwarfism are not diagnosed until they are about 3 years of age.
Medical professionals typically diagnose the fetus
as being small for the gestational age, or as having intrauterine growth disability when an ultrasound
is conducted. Typically, people with primoridal dwarfism are born with very low birth weight
s. After birth, growth continues at a stunted rate, leaving individuals with primordial dwarfism perpetually years behind their peers in stature and in weight.
Most cases of short stature are caused by skeletal or endocrine disorders. The five subtypes of primordial dwarfism are the most severe forms of the 200 types of dwarfism, and it is estimated that there are only 100 individuals in the world with the disorder. Other sources list the number of persons currently afflicted as high as 100 in North America.
It is rare for individuals affected by primordial dwarfism to live past the age of 30. In the case of microcephalic osteodysplastic primordial dwarfism (MOPD) type II there can be increased risk of vascular problems, which may cause premature death.
, as in hypopituitary dwarfism. Administering growth hormone, therefore, has little or no effect on the growth of the individual with primordial dwarfism. In January 2008, it was published that mutations in the pericentrin gene (PCNT
) were found to cause primordial dwarfism. Pericentrin has a role in cell division, proper chromosome segregation, and cytokinesis.
Dwarfism
Dwarfism is short stature resulting from a medical condition. It is sometimes defined as an adult height of less than 4 feet 10 inches , although this definition is problematic because short stature in itself is not a disorder....
that results in a smaller body size in all stages of life beginning from before birth
Birth
Birth is the act or process of bearing or bringing forth offspring. The offspring is brought forth from the mother. The time of human birth is defined as the time at which the fetus comes out of the mother's womb into the world...
. More specifically, primordial
Primordial
Primordial may refer to:* Primordial sea . See abiogenesis* Primordial nuclide, nuclides, a few radioactive, that formed before the Earth existed and are stable enough to still occur on Earth...
dwarfism is a diagnostic category including specific types of profoundly proportionate dwarfism, in which individuals are extremely small for their age, even as a fetus. Most individuals with primordial dwarfism are not diagnosed until they are about 3 years of age.
Medical professionals typically diagnose the fetus
Fetus
A fetus is a developing mammal or other viviparous vertebrate after the embryonic stage and before birth.In humans, the fetal stage of prenatal development starts at the beginning of the 11th week in gestational age, which is the 9th week after fertilization.-Etymology and spelling variations:The...
as being small for the gestational age, or as having intrauterine growth disability when an ultrasound
Ultrasound
Ultrasound is cyclic sound pressure with a frequency greater than the upper limit of human hearing. Ultrasound is thus not separated from "normal" sound based on differences in physical properties, only the fact that humans cannot hear it. Although this limit varies from person to person, it is...
is conducted. Typically, people with primoridal dwarfism are born with very low birth weight
Birth weight
Birth weight is the body weight of a baby at its birth.There have been numerous studies that have attempted, with varying degrees of success, to show links between birth weight and later-life conditions, including diabetes, obesity, tobacco smoking and intelligence.-Determinants:There are...
s. After birth, growth continues at a stunted rate, leaving individuals with primordial dwarfism perpetually years behind their peers in stature and in weight.
Most cases of short stature are caused by skeletal or endocrine disorders. The five subtypes of primordial dwarfism are the most severe forms of the 200 types of dwarfism, and it is estimated that there are only 100 individuals in the world with the disorder. Other sources list the number of persons currently afflicted as high as 100 in North America.
It is rare for individuals affected by primordial dwarfism to live past the age of 30. In the case of microcephalic osteodysplastic primordial dwarfism (MOPD) type II there can be increased risk of vascular problems, which may cause premature death.
Diagnosis
Since primordial dwarfism disorders are extremely rare, misdiagnosis is common. Because children with PD do not grow like other children, poor nutrition, a metabolic disorder, or a digestive disorder may be diagnosed initially. The correct diagnosis of PD may not be made until the child is 5 years old and it becomes apparent that the child has severe dwarfism.Types of primordial dwarfism
| Name | OMIM | Description |
|---|---|---|
| Seckel Syndrome Seckel syndrome The Seckel syndrome or microcephalic primordial dwarfism is a congenital nanosomic disorder.... |
People with Seckel Syndrome are noted to have microcephaly Microcephaly Microcephaly is a neurodevelopmental disorder in which the circumference of the head is more than two standard deviations smaller than average for the person's age and sex. Microcephaly may be congenital or it may develop in the first few years of life... . Many also suffer from scoliosis Scoliosis Scoliosis is a medical condition in which a person's spine is curved from side to side. Although it is a complex three-dimensional deformity, on an X-ray, viewed from the rear, the spine of an individual with scoliosis may look more like an "S" or a "C" than a straight line... , hip dislocation, delayed bone age, radial head dislocation, and seizures. Mutations in patients with Seckel syndrome have recently been identified in the gene encoding centrosomal protein CEP152, which is also mutated in some cases of primary isolated microcephaly. |
|
| Osteodysplastic Primordial Dwarfism, Type I (ODPDI) | This form of primordial dwarfism is often shortened to ODPDI. The corpus callosum Corpus callosum The corpus callosum , also known as the colossal commissure, is a wide, flat bundle of neural fibers beneath the cortex in the eutherian brain at the longitudinal fissure. It connects the left and right cerebral hemispheres and facilitates interhemispheric communication... of the brain is often undeveloped (called agenesis of the corpus callosum Agenesis of the corpus callosum Agenesis of the corpus callosum is a rare birth defect in which there is a complete or partial absence of the corpus callosum. Agenesis of the corpus callosum occurs when the corpus callosum, the band of white matter connecting the two hemispheres in the brain, fails to develop normally,... ) and patients are known to have seizures Epilepsy Epilepsy is a common chronic neurological disorder characterized by seizures. These seizures are transient signs and/or symptoms of abnormal, excessive or hypersynchronous neuronal activity in the brain.About 50 million people worldwide have epilepsy, and nearly two out of every three new cases... and apnea Apnea Apnea, apnoea, or apnœa is a term for suspension of external breathing. During apnea there is no movement of the muscles of respiration and the volume of the lungs initially remains unchanged... . Hair thinness is also common, including scalp, hair, eyelashes and eyebrows. They suffer skeletally from a short vertebrae, elongated clavicles, bent femora and hip displacement. Like those with Seckel Syndrome they also often have microcephaly Microcephaly Microcephaly is a neurodevelopmental disorder in which the circumference of the head is more than two standard deviations smaller than average for the person's age and sex. Microcephaly may be congenital or it may develop in the first few years of life... . |
|
| Osteodysplastic Primordial Dwarfism, Type II (ODPDII) | Those who have ODPDII often have further medical issues than the other types such as a squeaky voice, microdontia Microdontia Microdontia is a condition in which teeth appear smaller than normal. In the generalized form, all teeth are involved. In the localized form, only a few teeth are involved. The most common teeth affected are the upper lateral incisors and third molars... , widely spaced primary teeth, poor sleep patterns (in early years), delayed mental development, frequent sickness, breathing problems, eating problems, hyperactivity, farsightedness, brain aneurysm Aneurysm An aneurysm or aneurism is a localized, blood-filled balloon-like bulge in the wall of a blood vessel. Aneurysms can commonly occur in arteries at the base of the brain and an aortic aneurysm occurs in the main artery carrying blood from the left ventricle of the heart... s, and do not respond to hormone therapy because primordial dwarfism is not caused by a lack of any growth hormone Growth hormone Growth hormone is a peptide hormone that stimulates growth, cell reproduction and regeneration in humans and other animals. Growth hormone is a 191-amino acid, single-chain polypeptide that is synthesized, stored, and secreted by the somatotroph cells within the lateral wings of the anterior... . After reviewing x-rays it is also found that many have dislocated joints, scoliosis Scoliosis Scoliosis is a medical condition in which a person's spine is curved from side to side. Although it is a complex three-dimensional deformity, on an X-ray, viewed from the rear, the spine of an individual with scoliosis may look more like an "S" or a "C" than a straight line... , and delayed bone age as well as microcephaly Microcephaly Microcephaly is a neurodevelopmental disorder in which the circumference of the head is more than two standard deviations smaller than average for the person's age and sex. Microcephaly may be congenital or it may develop in the first few years of life... . They will not reach the size of an average newborn until they are between the ages of 3-5. |
|
| Russell-Silver Syndrome | The final height of those with Russell-Silver Syndrome often exceeds the height of others with primordial dwarfism, and they are very different. Some phenotypes (characteristics) of people who have Russell-Silver Syndrome are inadequate catch-up growth in first 2 years, body asymmetry, lack of appetite, low-set posteriorly rotated ears, clinodactly (inward curving) of the 5th finger, webbed toes, non-descended testicles (in males), weak muscle tone, delayed bone age, downturned corners of mouth & thin upper lip, hypospadias Hypospadias Hypospadias is a birth defect of the urethra in the male that involves an abnormally placed urinary meatus... , high pitched voice, small chin, delayed closure of the fontanel, hypoglycemia Hypoglycemia Hypoglycemia or hypoglycæmia is the medical term for a state produced by a lower than normal level of blood glucose. The term literally means "under-sweet blood"... , and a bossed forehead. Their heads may appear to be triangular shaped and large for their small body size. |
|
| Meier-Gorlin syndrome | Individuals with Meier-Gorlin Syndrome often have small ears and no kneecaps. They are also found to have curved clavicles, narrow ribs, and elbow dislocation. Like Russel-Silver Syndrome, they usually exceed the height of those with Seckel Syndrome and ODPDI and II. It is also known as "ear, patella, short stature syndrome" (EPS). Mutations in patients with Meier-Gorlin syndrome have recently been identified in a series of genes involved in chromosomal replication, specifically in the pre-replication complex Pre-replication complex A pre-replication complex is a protein complex that forms at the origin of replication during the initiation step of DNA replication. Formation of the pre-RC is required for DNA replication to occur. Complete and faithful replication of the genome ensures that each daughter cell will carry the... . Specific genes include origin recognition complex genes ORC1, ORC4 and ORC6, as well as other replication genes CDT1 and CDC6. |
Causes and treatment
There are as yet no effective treatments for primordial dwarfism. It is known that PD is caused by inheriting a mutant gene from each parent. The lack of normal growth in the disorder is not due to a deficiency of growth hormoneGrowth hormone
Growth hormone is a peptide hormone that stimulates growth, cell reproduction and regeneration in humans and other animals. Growth hormone is a 191-amino acid, single-chain polypeptide that is synthesized, stored, and secreted by the somatotroph cells within the lateral wings of the anterior...
, as in hypopituitary dwarfism. Administering growth hormone, therefore, has little or no effect on the growth of the individual with primordial dwarfism. In January 2008, it was published that mutations in the pericentrin gene (PCNT
PCNT
Pericentrin , also known as PCNT, is a protein which in humans is encoded by the PCNT gene.- Function :The protein encoded by this gene binds to calmodulin and is expressed in the centrosome. It is an integral component of the pericentriolar material...
) were found to cause primordial dwarfism. Pericentrin has a role in cell division, proper chromosome segregation, and cytokinesis.
Notable people believed to have primordial dwarfism
- Nelson de la RosaNelson de la RosaNelson Aquino de la Rosa , a.k.a. Mahow, was one of the shortest men of the 20th and 21st centuries and an actor from the Dominican Republic. Nelson measured 71 centimeters tall ....
- late actor linked to US baseball team the Boston Red SoxBoston Red SoxThe Boston Red Sox are a professional baseball team based in Boston, Massachusetts, and a member of Major League Baseball’s American League Eastern Division. Founded in as one of the American League's eight charter franchises, the Red Sox's home ballpark has been Fenway Park since . The "Red Sox"...
. - Lucia ZarateLucia ZarateLucia Zarate was born in San Carlos, today the area encompassing the town of Ursulo Galvan, Veracruz, and settled on the Agostadero, now Cempoala, Veracruz, Mexico. is the first person to have been identified with Majewski Osteodysplastic Primordial Dwarfism Type II. She was entered into the...
- first person identified to have MOPD II. - Weng WengWeng WengErnesto de la Cruz , better known as Weng Weng, was a Filipino actor and martial artist. Only 83 cm tall, he is listed in the Guinness World Records as the shortest adult actor in a leading role...
- late Filipino actor and martial artist - Aditya DevAditya DevAditya 'Romeo' Dev is an Indian body builder with dwarfism made famous by being reported in the UK press in February 2008. Romeo can shoulder press custom made 2 kg dumbbells, a notable feat given his 9 kg body weight and 84 cm stature...
- world's smallest bodybuilder - Gul MohammedGul MohammedGul Mohammed of New Delhi, India, according to The Guinness Book of World Records, was the shortest adult human being whose existence and height have been independently verified....
- smallest man of all time - He PingpingHe PingpingHe Pingping was, according to the Guinness World Records, the world's shortest man who was able to walk.- Early and personal life :He measured 74 cm tall, and was the third child of a family in Huade county, in the city of Ulanqab in northern China's Inner Mongolia Autonomous Region. He had...
- world's shortest man until his death in 2010 - Khagendra Thapa MagarKhagendra Thapa MagarKhagendra Thapa Magar , son of Rup Bahadur and Dhana Maya Thapa Magar, was the shortest man in the world, measuring . Formerly the shortest teenager in the world, Magar took the title of shortest man from Edward Nino Hernandez when he turned 18 on October 14, 2010. Magar is a primordial dwarf...
- world's shortest man from his 18th birthday on 14 October 2010 - Ethan Massey- child with PD until he died of it in 2009 at the age of 8
See also
- GigantismGigantismGigantism, also known as giantism , is a condition characterized by excessive growth and height significantly above average...
- DwarfismDwarfismDwarfism is short stature resulting from a medical condition. It is sometimes defined as an adult height of less than 4 feet 10 inches , although this definition is problematic because short stature in itself is not a disorder....
- Psychogenic dwarfismPsychogenic dwarfismPsychosocial short stature or psychosocial dwarfism, sometimes called psychogenic or stress dwarfism or the eponymous Kaspar Hauser syndrome, is a growth disorder that is observed between the ages of 2 and 15, caused by extreme emotional deprivation or stress.The symptoms include decreased growth...
- List of people with dwarfism
External links
- Potentials Foundation - a non-profit group offering support to children with primordial dwarfism and their families
- PrimordialDwarfism.com - a website dedicated to supporting the families of those affected by primordial dwarfism
- Walking With Giants Foundation - a non-profit organisation supporting children, adults and families affected by primordial dwarfism from around the world
- Gary Parker Photography - dwarfism section, including primordial
- "Medical Mystery: The Smallest People in the World" by Jennifer Dorian, ABC News, 6 January 2007
- "Born this way:A rare form of dwarfism sets girl apart from her twin sister" by Jessica Ryen Doyle, Fox News, 23 June 2011. This girl's primoridal dwarfism might have a unique cause.
- "Mila a tiny but perfect baby,' The Edmonton Journal, 26 December 2006
- Rauch, Anita, et al. Mutations in the Pericentrin (PCNT) Gene Cause Primordial Dwarfism Science 8 February 2008, Vol. 319 no. 5864 pp. 816-819. DOI: 10.1126/science.1151174. Abstract: "Fundamental processes influencing human growth can be revealed by studying extreme short stature. Using genetic linkage analysis, we find that biallelicAlleleAn allele is one of two or more forms of a gene or a genetic locus . "Allel" is an abbreviation of allelomorph. Sometimes, different alleles can result in different observable phenotypic traits, such as different pigmentation...
loss-of-function mutations in the centrosomalCentrosomeIn cell biology, the centrosome is an organelle that serves as the main microtubule organizing center of the animal cell as well as a regulator of cell-cycle progression. It was discovered by Edouard Van Beneden in 1883...
pericentrin (PCNT) gene on chromosome 21q22.3 cause microcephalicMicrocephalyMicrocephaly is a neurodevelopmental disorder in which the circumference of the head is more than two standard deviations smaller than average for the person's age and sex. Microcephaly may be congenital or it may develop in the first few years of life...
osteodysplastic primordial dwarfism type II (MOPD II) in 25 patients. Adults with this rare inherited condition have an average height of 100 centimeters and a brain size comparable to that of a 3-month-old baby, but are of near-normal intelligenceIntelligenceIntelligence has been defined in different ways, including the abilities for abstract thought, understanding, communication, reasoning, learning, planning, emotional intelligence and problem solving....
. Absence of PCNT results in disorganized mitotic spindlesMitotic spindleIn cell biology, the spindle fibers are the structure that separates the chromosomes into the daughter cells during cell division. It is part of the cytoskeleton in eukaryotic cells...
and missegregation of chromosomesChromosomeA chromosome is an organized structure of DNA and protein found in cells. It is a single piece of coiled DNA containing many genes, regulatory elements and other nucleotide sequences. Chromosomes also contain DNA-bound proteins, which serve to package the DNA and control its functions.Chromosomes...
. MutationsMutationIn molecular biology and genetics, mutations are changes in a genomic sequence: the DNA sequence of a cell's genome or the DNA or RNA sequence of a virus. They can be defined as sudden and spontaneous changes in the cell. Mutations are caused by radiation, viruses, transposons and mutagenic...
in related genesGeneA gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...
are known to cause primary microcephaly (MCPH1, CDK5RAP2, ASPM, and CENPJ)."