how is trisomy x diagnosed

How are trisomy disorders diagnosed?

Your healthcare provider will identify a trisomy disorder based on which chromosome has a third copy, resulting in a numbered diagnosis. Since each chromosome has a different role in your body’s blueprint, where the third copy attaches can affect what genetic condition your baby will have. The most common trisomy conditions include:

How is Triple X syndrome diagnosed?

Triple X syndrome may also be discovered during prenatal testing to identify other genetic disorders. If triple X syndrome is suspected based on signs and symptoms, it can be confirmed by genetic testing — chromosome analysis using a blood sample.

How many chromosomes do you have with trisomy X?

However, females with trisomy X have 47 chromosomes, three of which are X chromosomes (47,XXX karyotype). Trisomy X is a genetic disorder, but it is not inherited. The presence of the extra X chromosome results from errors during the normal division of reproductive cells in one of the parents (nondisjunction during meiosis).

What is trisomy X syndrome?

It can also be referred to as trisomy X syndrome or 47,XXX. A trisomy is a genetic condition in which there are three copies of a chromosome. Males and females are usually born with 46 chromosomes total, arranged in 23 pairs. One copy of each chromosome in the pair comes from the mother, and the other copy in the pair comes from the father.

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Can triple X syndrome be detected?

Genetic testing of the fluid or tissue will show if there's an extra, third, X chromosome. If triple X syndrome is suspected after birth based on signs and symptoms, it can be confirmed by genetic testing.

Can triple X syndrome be detected before birth?

Triple X syndrome can be diagnosed before the baby is born, through chorionic villus sampling (CVS) or amniocentesis, and a blood test after she is born.

Is trisomy X considered a disability?

Your Trisomy X Syndrome Disability Case If you are disabled because of Trisomy X Syndrome that is so severe it prevents you from working, you may well be entitled to Social Security Disability benefits.

What does an extra X chromosome mean for a girl?

Trisomy X, also called triple X syndrome or 47,XXX, is characterized by the presence of an additional X chromosome in each of a female's cells. Although females with this condition may be taller than average, this chromosomal change typically causes no unusual physical features.

What is the most common viable trisomy disorder?

Trisomy 21 – Down syndrome The most common is Standard Trisomy 21, in which the father's sperm or the mother's egg cell contains the extra chromosome. In Mosaic Down syndrome, the extra chromosome spontaneously appears as the embryo develops.

What happens if you have an extra chromosome?

Chromosomal abnormalities can have many different effects, depending on the specific abnormality. For example, an extra copy of chromosome 21 causes Down syndrome (trisomy 21). Chromosomal abnormalities can also cause miscarriage, disease, or problems in growth or development.

What is the gender of YY?

Males with XYY syndrome have 47 chromosomes because of the extra Y chromosome. This condition is also sometimes called Jacob's syndrome, XYY karyotype, or YY syndrome. According to the National Institutes of Health, XYY syndrome occurs in 1 out of every 1,000 boys.

CAN XXY be a girl?

Generally, individuals possessing 47, XXY karyotype have male phenotype. However, in the present case in spite of the presence of Y chromosome and the normal SRY, SOX9, and ZFY genes, the individual has a female phenotype.

What is XXY gender?

A person's biological sex is determined by the sex chromosomes: females have two X chromosomes, or XX; most males have one X chromosome and one Y chromosome, or XY. Males with XXY syndrome are born with cells that have an extra X chromosome, or XXY.

What happens if you have an extra chromosome?

Chromosomal abnormalities can have many different effects, depending on the specific abnormality. For example, an extra copy of chromosome 21 causes Down syndrome (trisomy 21). Chromosomal abnormalities can also cause miscarriage, disease, or problems in growth or development.

How do abnormalities in chromosome happen?

Chromosome abnormalities usually occur when there is an error in cell division. There are two kinds of cell division, mitosis and meiosis. Mitosis results in two cells that are duplicates of the original cell. One cell with 46 chromosomes divides and becomes two cells with 46 chromosomes each.

What happens if you have 47 chromosomes?

This means they have 47 chromosomes instead of 46. Down syndrome, Edward syndrome and Patau syndrome are the most common forms of trisomy. Children affected by trisomy usually have a range of birth anomalies, including delayed development and intellectual disabilities.

What is Turner's syndrome caused by?

Turner syndrome, a condition that affects only females, results when one of the X chromosomes (sex chromosomes) is missing or partially missing. Turner syndrome can cause a variety of medical and developmental problems, including short height, failure of the ovaries to develop and heart defects.

How is trisomy X diagnosed?

Chromosome aneuploidies such as trisomy X are diagnosed via karyotype, the process in which chromosomes are tested from blood, bone marrow, amniotic fluid, or placental cells. As trisomy X generally has a mild or asymptomatic phenotype, most cases are never diagnosed. It is estimated that around 10% of cases of trisomy X are diagnosed in their lifetimes; many cases are ascertained coincidentally during prenatal testing via amniocentesis or chorionic villi sampling, which is routinely performed for advanced maternal age. Indications for postnatal testing for trisomy X include tall stature, hypotonia, developmental disability or neurodivergence, mild dysmorphic features such as hypertelorism or clinodactyly, and premature ovarian failure. As postnatal karyotyping generally occurs in the setting of clinical concern, postnatally diagnosed trisomy X tends to have a more severe phenotype than prenatal.

How does trisomy X occur?

Trisomy X occurs via a process called nondisjunction, where the normal process of cell division is interrupted and produces gametes with too many or too few chromosomes. Nondisjunction is a random occurrence, and most girls and women with trisomy X have no family histories of chromosome aneuploidy.

What is the simplest form of mosaic trisomy X?

The simplest form of mosaic trisomy X, with a 46,XX/47,XXX karyotype, has an attenuated presentation compared to full trisomy X . Cognitive development is more typical, with improved long-term life outcomes. Although the general profile is milder than that of a non-mosaic 47,XXX karyotype, 46,XX/47,XXX mosaicism is associated with a higher risk of chromosome anomalies in offspring than full trisomy X; some writers have recommended screening during pregnancy. The increased risk of abnormal offspring in mosaicism has been hypothesized to be a consequence of oocyte abnormality in 46,XX/47,XXX women not seen in full 47,XXX.

What is the karyotype of trisomy X?

Karyotype. Trisomy X, also known as triple X syndrome and characterized by the karyotype 47,XXX, is a chromosome disorder in which a female has an extra copy of the X chromosome. A relatively common disorder occurring in 1 in 1,000 women, trisomy X is rarely diagnosed; fewer than 10% of those with ...

How high is trisomy X in schizophrenia?

The prevalence of trisomy X in women with adult-onset schizophrenia is estimated to be around 1 in 400, compared to 1 in 1,000 in women as a whole; the prevalence in childhood onset schizophrenia is unclear, but may be as high as 1 in 40.

What percentage of Turner syndrome cases are mosaic?

Between 3% and 15% of females with Turner syndrome, defined by a karyotype with a single copy of the X chromosome, have a 47,XXX cell line. Mosaic karyotypes with both 45,X0 and 47,XXX cells are considered cases of Turner syndrome rather than trisomy X, but trisomy X mosaicism has a significant impact on the Turner syndrome phenotype. Non-mosaic Turner syndrome is characterized by failure to begin or complete puberty and primary amenorrhea, while 80–90% of women with 47,X0/47,XXX mosaicism begin puberty naturally and approximately 60–80% have spontaneous menses. Around two-thirds of 45,X0/47,XXX mosaics have clinically significant short stature, compared with virtually all women with non-mosaic Turner syndrome.

How does trisomy X affect girls?

Though girls with trisomy X usually have good relationships with peers, they trend towards immaturity; some behavioural issues in children with trisomy X are thought to be a consequence of the disconnect between apparent age, as understood via increased height, and cognitive and emotional maturity encouraging hard-to-reach expectations. Girls whose motor and language skills are more severely affected by trisomy X often experience low confidence and self-esteem. These traits vary in severity; though some women with trisomy X are significantly impaired, many are within the normal range of variance, and some are high-functioning and high-achieving.

Diagnosis and Testing

Trisomy X can be diagnosed by chromosome analysis before a baby is born (prenatally) or after a baby is born (postnatally). The most common type of chromosome analysis used to diagnose trisomy X is known as a karyotype, which is essentially an organized image of the chromosomes within a cell obtained by microscopic evaluation.

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How is trisomy X diagnosed?from en.wikipedia.org

Chromosome aneuploidies such as trisomy X are diagnosed via karyotype, the process in which chromosomes are tested from blood, bone marrow, amniotic fluid, or placental cells. As trisomy X generally has a mild or asymptomatic phenotype, most cases are never diagnosed. It is estimated that around 10% of cases of trisomy X are diagnosed in their lifetimes; many cases are ascertained coincidentally during prenatal testing via amniocentesis or chorionic villi sampling, which is routinely performed for advanced maternal age. Indications for postnatal testing for trisomy X include tall stature, hypotonia, developmental disability or neurodivergence, mild dysmorphic features such as hypertelorism or clinodactyly, and premature ovarian failure. As postnatal karyotyping generally occurs in the setting of clinical concern, postnatally diagnosed trisomy X tends to have a more severe phenotype than prenatal.

What was the first term used to describe the karyotype of trisomy X?from en.wikipedia.org

The first description of trisomy X used the term 'superfemale' to describe the karyotype by analogy to Drosophilia flies, a term that was immediately disputed. Curt Stern proposed the use of 'metafemale', which Jacobs criticized as both medically inaccurate and an "illegitimate product of a Graeco-Roman alliance".

What is the simplest form of mosaic trisomy X?from en.wikipedia.org

The simplest form of mosaic trisomy X, with a 46,XX/47,XXX karyotype, has an attenuated presentation compared to full trisomy X . Cognitive development is more typical, with improved long-term life outcomes. Although the general profile is milder than that of a non-mosaic 47,XXX karyotype, 46,XX/47,XXX mosaicism is associated with a higher risk of chromosome anomalies in offspring than full trisomy X; some writers have recommended screening during pregnancy. The increased risk of abnormal offspring in mosaicism has been hypothesized to be a consequence of oocyte abnormality in 46,XX/47,XXX women not seen in full 47,XXX.

How high is trisomy X in schizophrenia?from en.wikipedia.org

The prevalence of trisomy X in women with adult-onset schizophrenia is estimated to be around 1 in 400, compared to 1 in 1,000 in women as a whole; the prevalence in childhood onset schizophrenia is unclear, but may be as high as 1 in 40.

What percentage of Turner syndrome cases are mosaic?from en.wikipedia.org

Between 3% and 15% of females with Turner syndrome, defined by a karyotype with a single copy of the X chromosome, have a 47,XXX cell line. Mosaic karyotypes with both 45,X0 and 47,XXX cells are considered cases of Turner syndrome rather than trisomy X, but trisomy X mosaicism has a significant impact on the Turner syndrome phenotype. Non-mosaic Turner syndrome is characterized by failure to begin or complete puberty and primary amenorrhea, while 80–90% of women with 47,X0/47,XXX mosaicism begin puberty naturally and approximately 60–80% have spontaneous menses. Around two-thirds of 45,X0/47,XXX mosaics have clinically significant short stature, compared with virtually all women with non-mosaic Turner syndrome.

How does trisomy X affect girls?from en.wikipedia.org

Though girls with trisomy X usually have good relationships with peers, they trend towards immaturity; some behavioural issues in children with trisomy X are thought to be a consequence of the disconnect between apparent age, as understood via increased height, and cognitive and emotional maturity encouraging hard-to-reach expectations. Girls whose motor and language skills are more severely affected by trisomy X often experience low confidence and self-esteem. These traits vary in severity; though some women with trisomy X are significantly impaired, many are within the normal range of variance, and some are high-functioning and high-achieving.

How old is a woman with trisomy X?from en.wikipedia.org

The average age of menopause for women with trisomy X is 45 years , compared to 50 years for women with 46,XX karyotypes. POF is more common in women with trisomy X who also have autoimmune disorders.

What test is used to determine if a person has an extra X chromosome?

These tests can include: Karyotype or chromosome microarray: This is used to assess the person for the presence of an extra X chromosome and to determine the degree of mosaicism (if any).

How many copies of a chromosome are there in a trisomy?

A trisomy is a genetic condition in which there are three copies of a chromosome. Males and females are usually born with 46 chromosomes total, arranged in 23 pairs. One copy of each chromosome in the pair comes from the mother, and the other copy in the pair comes from the father.

How many chromosomes are in triple X?

For some girls and women with triple X syndrome, all of their cells contain three X chromosomes. In other females with triple X syndrome, some cells have three X chromosomes while other have the usual two X chromosomes — this is referred to as mosaicism. The degree of mosaicism (the number of cells with three X chromosomes) may vary from a small percentage to close to 100%.

How many chromosomes are in a 23rd chromosome?

Triple X syndrome happens when a female is born with an extra X chromosome, and therefore has a total of 47 chromosomes . For some girls and women with triple X syndrome, ...

What are the most common disorders that girls with triple X syndrome have?

Attention deficit disorder: It’s more likely that girls with triple X syndrome will have difficulty concentrating in school than girls without triple X syndrome. Mood disorders: Mood disorders most commonly include anxiety and depression.

Why do women get triple X syndrome?

Most cases are caused by errors in chromosome replication and division during the formation of egg or sperm cells, and occur completely by chance. Mothers of advanced maternal age (women who are greater than 35 years old at the time of delivery) appear to be at an increased risk to have a daughter with triple X syndrome.

What are the social problems of triple X syndrome?

Social problems: Girls with triple X syndrome may have problems with communication or social interactions. They may be prone to low self-esteem. Mild cognitive or intellectual impairment: IQ is often in the normal range and typically only 10 to 15 points lower than siblings.

How to confirm triple X syndrome?

If triple X syndrome is suspected based on signs and symptoms, it can be confirmed by genetic testing — chromosome analysis using a blood sample. In addition to genetic testing, genetic counseling can help you gain comprehensive information about triple X syndrome.

How to help a child with X and Y chromosome disorders?

Connect with others. Support groups provide help and support for people with X and Y chromosome disorders and their families. They offer information and advice on coping, as well as ways to meet and talk with others in similar situations. Ask your child's doctor or therapist if there is a local support group for people with similar types of disorders. You can also contact AXYS — Association for X and Y Chromosome Variations.

What information do you need to know about your pregnancy?

Key personal information about your pregnancy, including any significant illnesses you may have experienced or any medications that you may have used. Any problems your child may be having with learning, emotions or behavior. Questions to ask your child's doctor.

Can triple X syndrome be discovered?

Because many girls and women with triple X syndrome are healthy and show no outward signs of the condition, they may remain undiagnosed all their lives, or the diagnosis may be discovered while checking other issues. Triple X syndrome may also be discovered during prenatal testing to identify other genetic disorders.

Can triple X be repaired?

The chromosome error that causes triple X syndrome can't be repaired, so the syndrome itself has no cure. Treatment is based on symptoms and needs. Options that may be helpful include: Periodic screenings. The doctor may recommend periodic screenings throughout childhood and into adulthood.

How many chromosomes are in triple X syndrome?

Females normally have two X chromosomes in all cells — one X chromosome from each parent. In triple X syndrome, a female has three X chromosomes.

What are the symptoms of triple X syndrome?

Signs and symptoms in girls and women with triple X syndrome may include an increased risk of: Delayed development of speech and language skills, as well as motor skills, such as sitting up and walking. Learning disabilities, such as difficulty with reading (dyslexia), understanding or math.

Why is triple X syndrome called 47,XXX syndrome?

Triple X syndrome is also called 47,XXX syndrome because the extra X chromosome results in 47 chromosomes in each cell instead of the usual 46.

What determines a child's sex?

The pair of sex chromosomes — either XX or XY — determines a child's sex. A mother can give the child only an X chromosome, but a father can pass on an X or a Y chromosome: If the child receives an X chromosome from the father, the XX pair makes the child genetically a female.

Why is triple X syndrome not inherited?

Causes. Although triple X syndrome is genetic, it's usually not inherited — it's due to a random genetic error. Normally, people have 46 chromosomes in each cell, organized into 23 pairs, including two sex chromosomes. One set of chromosomes is from the mother and the other set is from the father. These chromosomes contain genes, which carry ...

What is mosaic chromosome?

Mosaic. Occasionally, the extra chromosome results from an incorrect cell division caused by a random event early in the embryo's development. If this is the case, the child has a mosaic form of triple X syndrome, and only some cells have the extra X chromosome. Females with the mosaic form may have less obvious symptoms.

What does XY mean in genetics?

If the child receives a Y chromosome from the father, the XY pair means the child is genetically a male.

What is the treatment for trisomy X?

Early intervention strategies, like speech therapy, physical therapy, and occupational therapy, can help some girls with trisomy X catch up to their peers or reach their full potential. (5)

What is trisomy X?

In most cases, trisomy X occurs when the cells from the mother’s egg or the father’s sperm divide incorrectly, creating an egg or sperm that has an extra X chromosome. In women with mosaicism, the extra chromosome arises from an incorrect cell division that randomly occurs when the embryo (the fertilized egg) develops.

What is triple X syndrome?

Triple X syndrome — also called trisomy X or 47,XXX — is a genetic disorder in which a woman carries an extra X chromosome in each of her cells. Although it’s a genetic disorder, triple X syndrome (which only affects women) is almost never inherited. People have 46 chromosomes in each cell, ...

How many chromosomes are in triple X?

Although it’s a genetic disorder, triple X syndrome (which only affects women) is almost never inherited. People have 46 chromosomes in each cell, including one pair of sex chromosomes. Normally, women have two X chromosomes (XX) per cell, while men have one X and one Y chromosome (XY), according to the National Institutes of Health. ...

What does 47 XYY mean?

48,XXYY: a chromosome condition in males that results from having an extra X and Y chromosome. 48,XXXY: a chromosome condition in males that results from having two extra X chromosomes.

How to diagnose triple X syndrome?

Triple X syndrome can also be diagnosed before birth with noninvasive prenatal testing (NIPT), which can determine whether the fetus is at risk for chromosomal disorders. If the test shows an increased risk, the diagnosis can be confirmed with an amniocentesis, a test that analyzes the amniotic fluid surrounding the fetus, or a chorionic villus sampling (CVS), which removes a tissue sample from the placenta.

Can trisomy X be a problem?

Some girls with trisomy X may have attention disorders and be more prone to anxiety, particularly when they’re in school. Support groups can help girls cope with some of the emotional difficulties they may be experiencing, as can switching to a smaller classroom or being home-schooled part-time. (5)

What is trisomy?

Trisomy is a genetic condition where there is an extra copy of a chromosome. Chromosomes are structures within the nucleus of cells that carry DNA, which is a thread-like structure that makes you unique. Your body has 23 pairs of chromosomes, which equals 46 total chromosomes. You acquire half of your chromosomes from each of your parents.

How do you pronounce trisomy?

The correct pronunciation of trisomy is “try-sow-me.” When a number follows trisomy, that designates which chromosome has a third copy. The pronunciation stays the same in both references, with the addition of the number that follows, for example, “trisomy 21” is “try-sow-me-twenty-one.”

What are the different types of trisomy disorders?

Your healthcare provider will identify a trisomy disorder based on which chromosome has a third copy, resulting in a numbered diagnosis. Since each chromosome has a different role in your body’s blueprint, where the third copy attaches can affect what genetic condition your baby will have. The most common trisomy conditions include:

Who does trisomy affect?

Trisomy can occur in any pregnancy. The risk is higher in those over 35 years old who become pregnant, but the majority of babies born with trisomy are to parents younger than 35 years of age because there are statistically more births in those under 35 years.

How common is trisomy?

The most common type of trisomy is trisomy 21 (Down syndrome). There are nearly 6,000 babies born with trisomy 21 each year in the United States, which equals about 1 in 700 babies.

What are the symptoms of trisomy during pregnancy?

During a prenatal ultrasound, your healthcare provider will look for signs of trisomy conditions including:

What are the symptoms of trisomy after my baby is born?

Depending on the type of trisomy diagnosed, your baby will have symptoms including:

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