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An inherited disease characterized by short stature , facial abnormalities, and genital abnormalities.
Aase syndrome is a rare genetic disorder that may be detected during early infancy.
Ablepharon Macrostomia Syndrome is an extremely rare inherited genetic disorder that is characterized by different physical abnormalities that affect the head and facial areas, skin, fingers, and the genitalia.
Hypoplasia of the hepatic ducts, congenital pulmonary artery stenosis, facial abnormalities, and other congenital malformations, particularly skeletal.
Monosomy 9P, otherwise known as Alfi's Syndrome or 9P-, is a rare chromosome anomaly affecting about one birth in five million. The disorder consists of mental retardation, sociable personality, trigonocephaly, mongoloid eyes, wide flat nasal bridge, anteverted nostrils, long upper lip, short neck, long digits mostly secondary to long middle phalanges, and predominance of whorls on fingers. Because of its extreme rarity, it is little-studied and little-known.
Barth Syndrome is a rare but serious genetic disorder that affects males.
Features include: macroglossia, a large tongue which may cause breathing, feeding or speech difficulties; umbilical hernia or exomphalos; overgrowth, children are bigger than their contemporaries; hemihypertrophy, one side of the body grows more than the other; hypoglycaemia, low blood sugar as babies; characteristic facial appearance and indentations of the ears.
Bloom's syndrome is inherited as an autosomal recessive disease, typically manifesting itself as: unusually small size at birth but otherwise a normal degree of maturation; shortness of stature after birth, only rarely reaching five feet; redness of the skin of the face, mainly the bridge of the nose and the adjoining upper cheek areas, the lower eyelids, and the lower lip; and increased numbers of respiratory tract and ear infections, some of which are life-threatening.
Cohen syndrome is an extremely variable genetic disorder characterized by diminished muscle tone (hypotonia), abnormalities of the head, face, hands and feet and mental retardation.
Costello Syndrome is an extremely rare disorder characterized by growth delay after birth (postnatal), leading to short stature; excessive, redundant loose skin on the neck, palms of the hands, fingers, and soles of the feet; development of benign (non-cancerous) growths (papillomata) around the mouth (perioral) and nostrils (nares); mental retardation; and/or characteristic facial appearance.
Cystic Fibrosis is an inherited disease of the exocrine glands, affecting the pancreas, respiratory system, and sweat glands. Usually beginning in infancy, it is characterized by chronic respiratory infections, pancreatic insufficiency, and susceptibility to heat prostration.
Cirrhosis of the liver, occurring in childhood, is common and may produce portal hypertension, splenomegaly, and hypersplenism.
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History of Down Syndrome
In 1866, a physician named John Langdon Down first described a set of children with common features who were distinct from other children with developmental delays. Dr. Down was superintendent of a facility for children with developmental delays in Surrey, England when he made this distinction.
In 1959, a French physician named Jerome Lejune discovered the genetic cause of Down Syndrome, observing 47 chromosomes per cell.
Cause of Down Syndrome
There are three types of chromosomal abnormalities that cause Down Syndrome.
In every cell of a normal person's body, there are 46 chromosomes, 23 pairs. They receive half of these chromosomes from their father, half from their mother. When the sperm and egg each divide in two, in preparation for fertilization, the chromosome pairs are also supposed to divide, one side going to each cell. This is called disjunction.
Standard Trisomy 21
The first type of chromosomal abnormality that causes Down Syndrome happens when either the sperm or the egg divides wrongly. All the chromosomes except one divide correctly. In Down Syndrome, that one is the 21st chromosome. The entire 21st pair goes over to one side. After conception, there are then three total copies of the 21st chromosome, instead of the two in normal persons. As the child develops, the extra chromosome is replicated in every cell of the body. The medical term for this is Trisomy 21, or nondisjunction. It accounts for about 95% of the causes of Down Syndrome.
Translocation Trisomy 21
In the second type of chromosomal abnormality that causes Down Syndrome an extra part of chromosome 21 is attached or stuck onto another chromosome. There are still only 46 chromosomes, but the extra part of number 21 is producing extra genetic products, resulting in Down Syndrome.
This form is usually inherited from a parent. Sometimes a person has only one normal 21st chromosome besides the translocated one. Such a person does not have Down Syndrome. However, if one of their children has two normal 21st chromosomes, besides the extra, that extra chromosome part is producing extra genetic products, and results in Down Syndrome. This type is called translocation trisomy 21. It accounts for about 3-4% of the causes of Down Syndrome.
Mosaic Trisomy 21
In the third type of chromosomal abnormality, some of the cells have a trisomy, with 47 total chromosomes, and other cells will have the normal 46 chromosomes. There have been proposed two ways that this might happen.
One of the ways is that when the child was conceived, the very first cell division went wrong, the same as in standard trisomy 21. However, a little farther down the line, there was yet another error, resulting in the normal 46 chromosomes for that line of cells. If the second error occurred when there were only 2 cells, 1/2 of the chromosomes would have 46 chromosomes, and one half would have 47. If the error occurred when there were 4 cells, 1/4 of the cells would have 46 chromosomes, and 3/4 would have 47.
Another of the ways suggested is that the first cell division is normal. However, nondisjunction of the 21st chromosome occurred later on. If it occurred when there were only 2 cells, 1/2 of the cells would have 47 chromosomes. If it occurred when there were 4 cells, 1/4 of the cells would have the trisomy. This type, no matter how it happened, is called mosaic trisomy 21. It accounts for about 1-2% of the causes of Down Syndrome.
Since only part of the cells have a trisomy, there is not as much of the extra genetic products being produced. Therefore, depending on the percentage of trisomic cells, this child might not have as many problems as someone with standard Trisomy 21, who has all trisomic cells.
Regardless of the type of trisomy, all these people have an extra chromosome, meaning that there are extra genes producing extra genetic products. Those extra genetic products produce what we know as Down Syndrome.
Trisomy 21 occurs once in every 800 to 1000 births in the United States.
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A syndrome of intrauterine dwarfism, short stature, mental retardation, sparse hair, eczema, and characteristic facies. The phenotype varies from normal growth and head circumference with mild psychomotor retardation and lack of eczema to severe growth and mental retardation, microcephaly, behavioral problems, aplastic anemia, immunological disorders, neoplasms, and eczema Some features of this syndrome are similar to those in Bloom and fetal alcohol syndromes.
A very rare disorder characterized by short stature, delayed language skills, and a triangular shaped face. A broad nose, deep-set eyes and a wide mouth with thin lips give the affected patient a distinct appearance.
Refers to a group of genetic disorders that are characterized by progressive weakness and spasticity (stiffness) of the legs.
Hutchinson-Gilford Progeria Syndrome is a very rare genetic condition, causing greatly accelerated ageing. There is a genetic test, but, as of May 2013, no cure.
Hydrolethalus syndrome is a severe complex malformation syndrome, which leads to death of the fetus in most cases in utero, or immediately after the birth. The causative gene, still waiting to be cloned, is located at chromosome 11q23-q25. The characteristic malformations are external asymmetric hydrocephalus, a keyhole-shaped foramen magnum and polydactyly in all extremities. Other common findings are poorly developed mandible, small, often bifid nose and hypoplastic eyes. Atrioventricular communis defect of the heart is frequently found as well as abnormal lobation of the lungs. Careful clinical examination provides the diagnosis of the hydrolethalus syndrome distinct from Meckels syndrome. Prenatal diagnosis by ultrasound can be established already at 12th week of gestation.
Langer-Giedion syndrome is a rare autosomal dominant genetic disorder caused by a deletion of chromosomal material. Associated features include learning difficulties, short stature, distinctive facial features, small head and skeletal abnormalities
Laurence-Moon Syndrome is a rare inherited disorder characterized by diminished hormone production by the testes or ovaries (hypogonadism), progressive loss of vision (retinitis pigmentosa), mental retardation, and paralysis of the legs and lower part of the body accompanied by involuntary muscle contractions (spastic paraplegia).
Loeys-Dietz syndrome is a recently-discovered autosomal dominant genetic syndrome which has many features similar to Marfan syndrome, but which is caused by mutations in the genes encoding transforming growth factor beta receptor 1 (TGFBR1) or 2 (TGFBR2). It was identified and characterized by American physician Harry C. Dietz and Belgian physician Bart L. Loeys, for whom it is named.
From: Wikipedia: Loeys-Dietz Syndrome
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Also known as oculo-cerebro-renal syndrome, is a rare inherited metabolic disease that affects males.
A very rare genetic disease characterised by mandibular hypoplasia, deafness, progeroid features.
An autosomal recessive disorder with an increased incidence in the Jewish population that is invariably fatal at birth due to renal failure and pulmonary hypoplasia.
PLOSL is an adult-onset recessively inherited disorder of bones and central nervous system leading to early dementia and death. Recent studies have shown that the genetic basis of PLOSL is mutation(s) in the gene encoding a tyrosine kinase-binding protein TYROBP. Onset of clinical disease occurs in the third decade of life with pain and swelling following strain of the wrist and ankle. Fractures may occur after minor accidents. Neuropsychiatric symptoms begin after age of 30 years presenting progressive dementia with an accentuated prefrontal syndrome, signs of upper motor neuron involvement, agnostic-aparactic-aphasic symptoms, myoclonic jerks and epileptic seizures. Death occurs before the age 50.
A cardiofacial syndrome with a variable phenotype, which may change with age, many characteristics of which overlap those of the Turner syndrome. Short stature and mild mental retardation are the main features of this syndrome. Webbed neck, heart defects, chest deformities, characteristic facial features, and other abnormalities, and occasional hyperpyrexia may be associated. Cardiofaciocutaneous and Noonan syndromes are sometimes considered the same entity.
Opitz Syndrome is a genetic disorder that may be evident at birth.
A syndrome of hypothalamic hamartoblastoma, craniofacial abnormalities, polydactyly, and endocrine, cardiac, renal defects, and mild mental retardation in some cases.
Pallister-Killian Mosaic Syndrome is a rare chromosomal disorder that occurs for no apparent reason. Major symptoms may include a coarse face with a high forehead, sparse hair on the scalp, an abnormally wide space between the eyes, a fold of the skin over the inner corner of the eyes, and a broad nasal bridge with a highly arched palate. Mental retardation, loss of muscle tone, and streaks of skin lacking color are often present.
Popliteal Pterygium Syndrome is an extremely rare inherited disorder that is apparent at birth (congenital).
Prader–Willi syndrome is a rare genetic disorder in which up to seven genes on chromosome 15 are deleted or unexpressed on the paternal chromosome.
Progeria is a rare genetic condition characterized by an appearance of accelerated aging in children. Its name is derived from the Greek and means "prematurely old." The classic type is the Hutchinson-Gilford Progeria Syndrome which was first described in England in 1886 by Dr. Jonathan Hutchinson and again in 1886 and 1904 by Dr. Hastings Gilford.
Hamartoneoplastic malformation syndrome of uncertain etiology characterized by partial gigantism of the hands and/or feet, asymmetry of the limbs, plantar hyperplasia, hemangiomas, lipomas, lymphangiomas, epidermal nevi, macrocephaly, cranial hyperostoses, and long-bone overgrowth. Joseph Merrick, the so-called "elephant man", apparently suffered from Proteus syndrome and not neurofibromatosis, a disorder with similar characteristics.
Rubinstein-Taybi syndrome is a rare genetic multisystem disorder that affects many organ systems of the body.
Shwachman syndrome is a rare genetic disorder with multiple and varied manifestations. The disorder is typically characterized by signs of insufficient absorption (malabsorption) of fats and other nutrients due to abnormal development of the pancreas (pancreatic insufficiency) and improper functioning of the bone marrow (bone marrow dysfunction), resulting in low levels of circulating blood cells (hematologic abnormalities). Additional characteristic findings may include short stature; abnormal bone development affecting the rib cage and/or bones in the arms and/or legs (metaphyseal dysostosis); and/or liver abnormalities.
Smith-Magenis Syndrome is a rare chromosomal disorder characterized by abnormalities of the head and facial (craniofacial) area, delays in the acquisition of skills requiring the coordination of mental and muscular activities (psychomotor retardation), mental retardation, speech delays, and/or behavioral abnormalities.
A rare disorder inherited as an autosomal recessive genetic trait. Characteristic features of this disorder include progressive loss of vision and hearing beginning in early childhood, diabetes mellitus, and obesity.
Informational sites about triploidy, a chromosomal abnormality.
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VACTERL Association is a sporadic, non-random association of specific birth defects. The word VACTERL is an acronym, where each letter of the word relates to an area of abnormalities. Formally known as VATER Syndrome, this condition is now generally termed as VACTERL due to the addition of other areas of defects known to be connected with the condition.
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VCFS -- also known as the Shprintzen Syndrome, DiGeorge Sequence and, regrettably, Catch 22 -- is caused by the deletion of a small segment of the long arm of chromosome 22 (specified as 22q11.2 deletion), and is one of the most common genetic disorders in humans. Velo-Cardio-Facial syndrome is characterized by cleft palate, heart abnormalities, learning disabilities, and over 180 other clinical findings
The Waardenburg syndrome (WS) gene affects the body in three primary ways: hearing , pigmentation (coloring) of the skin, hair and eyes, and facial structure.
Weaver Syndrome is characterized by rapid growth. Usually starting before birth (prenatal onset), physical growth and bone development (maturation) can occur more quickly than average.