Turner syndrome

45,Xmonosomy XTurnerTurnersX045, Xmonosomy X (Turner syndrome)Turner's SyndromeTurner's syndrome (XO)Turner-like
Turner syndrome (TS), also known as 45,X or 45,X0, is a condition in which a female is partly or completely missing an X chromosome.wikipedia
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Congenital heart defect

congenital heart diseaseheart defectcongenital heart defects
Heart defects, diabetes, and low thyroid hormone occur more frequently.
A number of genetic conditions are associated with heart defects including Down syndrome, Turner syndrome, and Marfan syndrome.

Low-set ears

low set earslow-set
Often, a short and webbed neck, low-set ears, low hairline at the back of the neck, short stature, and swollen hands and feet are seen at birth.
Turner syndrome

Short stature

Shortshort final statureshort height
Often, a short and webbed neck, low-set ears, low hairline at the back of the neck, short stature, and swollen hands and feet are seen at birth.
Among children without growth hormone deficiency, short stature may be caused by Turner syndrome or Noonan syndrome, chronic renal insufficiency, being small for gestational age at birth, Prader–Willi syndrome, Wiedemann-Steiner syndrome, or other conditions.

Chromosome abnormality

chromosomal abnormalitieschromosome abnormalitieschromosomal abnormality
Turner syndrome is due to a chromosomal abnormality in which all or part of one of the X chromosomes is missing or altered.
An example of monosomy is Turner syndrome, where the individual is born with only one sex chromosome, an X.

Mosaic (genetics)

mosaicismmosaicgenetic mosaic
While most people have 46 chromosomes, people with TS usually have 45. The chromosomal abnormality may be present in just some cells in which case it is known as TS with mosaicism.
Around 30% of Turner's syndrome cases demonstrate mosaicism, while complete monosomy (45, X) occurs in about 50–60% of cases.

Henry Turner (endocrinologist)

Henry Turner
Henry Turner first described the condition in 1938.
Henry Hubert Turner (August 28, 1892 – August 4, 1970) was an American endocrinologist, noted for his published description of Turner syndrome in 1938 at the annual meeting of the Association for the Study of Internal Secretions.

X chromosome

Xchromosome XX-chromosome
Turner syndrome (TS), also known as 45,X or 45,X0, is a condition in which a female is partly or completely missing an X chromosome.
Turner syndrome:

Webbed neck

webbing of the neck
Often, a short and webbed neck, low-set ears, low hairline at the back of the neck, short stature, and swollen hands and feet are seen at birth. Webbed neck from cystic hygroma in infancy
It is a feature of Turner syndrome (only found in girls) and Noonan syndrome, as well as the rarer Klippel-Feil syndrome, or Diamond-Blackfan Anemia

Lymphedema

lymphoedemaelephantiasiscongenital lymphedema
Lymphedema (swelling) of the hands and feet of a newborn
Multiple syndromes are associated with primary lymphedema, including Turner syndrome, Milroy's disease, and Klippel-Trenaunay-Weber syndrome.

Amenorrhea

amenorrhoeaprimary amenorrheasecondary amenorrhea
Typically, they develop menstrual periods and breasts only with hormone treatment, and are unable to have children without reproductive technology. Turner syndrome is characterized by primary amenorrhoea, premature ovarian failure (hypergonadotropic hypogonadism), streak gonads and infertility (however, technology (especially oocyte donation) provides the opportunity of pregnancy in these patients).
Gonadal dysgenesis, often associated with Turner's Syndrome, or premature ovarian failure may also be to blame.

Cystic hygroma

Cystic hygromashygromalymphatic malformation
Webbed neck from cystic hygroma in infancy
Additionally, it can be associated with Down syndrome, Turner syndrome or with Noonan syndrome.

Coarctation of the aorta

aortic coarctationcoarctation of aortacoarctation
Coarctation of the aorta The higher rate in the group of pure 45,X monosomy is primarily due to a difference in the rate of aortic valve abnormalities and coarctation of the aorta, the two most common cardiovascular malformations.
1) Preductal coarctation: The narrowing is proximal to the ductus arteriosus. Blood flow to the aorta that is distal to the narrowing is dependent on the ductus arteriosus; therefore severe coarctation can be life-threatening. Preductal coarctation results when an intracardiac anomaly during fetal life decreases blood flow through the left side of the heart, leading to hypoplastic development of the aorta. This is the type seen in approximately 5% of infants with Turner syndrome.

Cubitus valgus

valgus
Other features may include a small lower jaw (micrognathia), cubitus valgus, soft upturned nails, palmar crease, and drooping eyelids.
When present at birth, it can be an indication of Turner syndrome or Noonan syndrome.

Bicuspid aortic valve

bicuspid valvecongenitally have two leaflets
Bicuspid aortic valve (most common cardiac problem)
. It is also the most observed cardiac defect in Turner syndrome.

Hypoplastic left heart syndrome

heart defecthypoplastic left
Hypoplastic left heart syndrome represents the most severe reduction in left-sided structures.
HLHS is also associated with several genetic syndromes, including trisomy 13 (Patau syndrome), trisomy 18 (Edwards syndrome), partial trisomy 9, Turner's syndrome (XO), Jacobsen syndrome (11q deletion syndrome), Holt-Oram syndrome, and Smith-Lemli-Opitz syndrome.

Hypothyroidism

hypothyroidhypo-underactive thyroid
Heart defects, diabetes, and low thyroid hormone occur more frequently. Usually it is hypothyroidism, specifically Hashimoto's thyroiditis.
There is a much higher rate of thyroid disorders, the most common of which is hypothyroidism, in individuals with Down syndrome and Turner syndrome.

Osteoporosis

bone lossosteoporoticpostmenopausal osteoporosis
Due to inadequate production of estrogen, many of those with Turner syndrome develop osteoporosis.
Hypogonadal states can cause secondary osteoporosis. These include Turner syndrome, Klinefelter syndrome, Kallmann syndrome, anorexia nervosa, andropause, hypothalamic amenorrhea or hyperprolactinemia. In females, the effect of hypogonadism is mediated by estrogen deficiency. It can appear as early menopause (1 year). Bilateral oophorectomy (surgical removal of the ovaries) and premature ovarian failure cause deficient estrogen production. In males, testosterone deficiency is the cause (for example, andropause or after surgical removal of the testes).

Aortic valve

aorticaortic valvesaortic semilunar valve
The higher rate in the group of pure 45,X monosomy is primarily due to a difference in the rate of aortic valve abnormalities and coarctation of the aorta, the two most common cardiovascular malformations.
Turner syndrome, a congenital condition that affects females, can often have a bicuspid aortic valve as one of its symptoms.

Metacarpal bones

metacarpalmetacarpalsmetacarpus
Shortened metacarpal IV
A blunted fourth metacarpal, with normal fifth metacarpal, can signify Turner syndrome.

Gonadal dysgenesis

streak gonadstesticular dysgenesiscomplete gonadal dysgenesis
Turner syndrome is characterized by primary amenorrhoea, premature ovarian failure (hypergonadotropic hypogonadism), streak gonads and infertility (however, technology (especially oocyte donation) provides the opportunity of pregnancy in these patients).
Turner syndrome also known as 45,X or 45,X0

Miscarriage

miscarriedspontaneous abortionmiscarriages
Even when such pregnancies do occur, there is a higher than average risk of miscarriage or birth defects, including Turner syndrome or Down syndrome.
Common chromosome abnormalities found in miscarriages include autosomal trisomy (22-32%), monosomy X (5-20%), triploidy (6-8%), tetraploidy (2-4%), or other structural chromosomal abnormalities (2%).

Aortic dissection

dissecting aortic aneurysmdissectionthoracic aortic dissection
Even if not every aortic root dilatation necessarily goes on to an aortic dissection (circumferential or transverse tear of the intima), complications such as dissection, aortic rupture resulting in death may occur.
Turner syndrome also increases the risk of aortic dissection, by aortic root dilatation.

Micrognathism

micrognathiaagnathiasmall lower jaw
Other features may include a small lower jaw (micrognathia), cubitus valgus, soft upturned nails, palmar crease, and drooping eyelids.
X0 syndrome (Turner syndrome)

Monosomy

monosomies
The abnormal cells may have only one X (monosomy) (45,X) or they may be affected by one of several types of partial monosomy like a deletion of the short p arm of one X chromosome (46,X,del(Xp)) or the presence of an isochromosome with two q arms (46,X,i(Xq)) Turner syndrome has distinct features due to the lack of pseudoautosomal regions, which are typically spared from X-inactivation.
Turner syndrome – People with Turner syndrome typically have one X chromosome instead of the usual two sex chromosomes. Turner syndrome is the only full monosomy that is seen in humans—all other cases of full monosomy are lethal and the individual will not survive development.

Hashimoto's thyroiditis

Hashimoto's diseasehashimoto diseaseHashimotos's disease
Usually it is hypothyroidism, specifically Hashimoto's thyroiditis.
The genes implicated vary in different ethnic groups and the incidence is increased in people with chromosomal disorders, including Turner, Down, and Klinefelter syndromes usually associated with autoantibodies against thyroglobulin and thyroperoxidase.