Klinefelter syndrome, XXY syndrome, is a term used to describe males who have an extra X - Bright Tots - Information on child development - Autism information.  www.brighttots.com
Klinefelter / XXY Syndrome
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Klinefelter syndrome, also known as the XXY syndrome, is a term used to describe males who have an extra X chromosome in
most of their cells. Instead of having the usual XY chromosome pattern that most males have, these men have an XXY pattern.

In 1942, Dr. Harry Klinefelter and his coworkers at the Massachusetts General Hospital in Boston published a report about nine
men who had enlarged breasts, sparse facial and body hair, small testes, and an inability to produce sperm. One of the largest of
these studies, sponsored by the National Institute of Child Health and Human Development (NICHD), checked the
chromosomes of more than 40,000 infants.

Based on these studies, the XXY chromosome arrangement appears to be one of the most common genetic abnormalities
known, occurring as frequently as 1 in 500 to 1 in 1,000 male births. Although the syndrome's cause, an extra sex
chromosome, is extensive, the syndrome itself-the set of symptoms and characteristics that may result from having the extra
chromosome, is rare. Many men live out their lives without ever even suspecting that they have an additional chromosome.

Even though all men with Klinefelter syndrome have the extra X chromosome, not every XXY male has all of those symptoms.
Because not every male with an XXY pattern has all the symptoms of Klinefelter syndrome, it is common to use the term
to describe these men, or XXY condition to describe the symptoms.  Scientists believe the XXY condition is one of the
most common chromosome abnormalities in humans.  About one of every 500 males has an extra X chromosome, but many
don’t show any symptoms.

Symptoms of Klinefelter Syndrome / XXY Condition

Most medical researchers prefer the term XXY condition than Klinefelter Syndrome. Most favor to describe men and boys
having the extra chromosome as "XXY males."
In addition to occasional breast enlargement, lack of facial and body hair, and a rounded body type, XXY males are more likely
than other males to be overweight, and tend to be taller than their fathers and brothers.
For the most part, these symptoms are treatable. Surgery, when necessary, can reduce breast size. Regular injections of the
male hormone testosterone, beginning at puberty, can promote strength and facial hair growth-as well as bring about a more
muscular body type.

A far more serious symptom, however, is one that is not always readily apparent. Although they are not mentally retarded, most
XXY males have some degree of language impairment. As children, they often learn to speak much later than do other children
and may have difficulty learning to read and write. And while they eventually do learn to speak and communicate normally, the
majority tends to have some degree of difficulty with language throughout their lives. If untreated, this language impairment can
lead to school failure and it’s associated to low self esteem.

Language Delay in Children with Klinefelter Syndrome

Shortly after the first birthday, children should be able to make their wishes known with simple one word utterances. For
example, a child may say "milk" to mean "I want more milk." Gradually, children begin to combine words to produce two-word
sentences, such as "More milk." By age three, most children use an average of about four words per sentence.

If a child is not communicating effectively with single words by 18 to 24 months, then parents should seek a consultation with
a speech and language pathologist. Fortunately, however, this language disability usually can be improved. Chances for success
are greatest if begun in early childhood.

Not all males with the condition have the same symptoms or to the same degree.  Symptoms depend on how many XXY cells a
man has, how much testosterone is in his body, and his age when the condition is diagnosed.

Early Language Problems

The parents of XXY babies can strengthen their children's language disability by providing special help in language development,
beginning at an early age. However, there is no easy procedure to meet the language needs of all XXY boys. Like everyone else,
XXY males are unique individuals. A few may not have any trouble learning to read and write, while the rest may have language
impairments ranging from mild to severe.

If their son's speech seems to be lagging behind that of other children, parents should ask their child's pediatrician for a referral
to a speech pathologist for further testing. A speech pathologist specializes in the disorders of voice, speech, and language.

Parents should also pay particular attention to their children's hearing. Like other small children, XXY infants and toddlers may
suffer from frequent ear infections. With any child, such infections may impair hearing and delay the acquirement of language.
Such a hearing impairment may be a further setback for an XXY child who is already having language difficulties.

The XXY condition can affect three main areas of development:

Physical development: As babies, many XXY males have weak muscles and reduced strength.  They may sit up, crawl, and
walk later than other infants.  After about age four, XXY males tend to be taller and may have less muscle control and
coordination than other boys their age.

As XXY males enter puberty, they often don’t make as much testosterone as other boys.  This can lead to a taller, less
muscular body, less facial and body hair, and broader hips than other boys.  As teens, XXY males may have larger breasts,
weaker bones, and a lower energy level than other boys.

By adulthood, XXY males look similar to males without the condition, although they are often taller.  They are also more likely
than other men to have certain health problems, such as autoimmune disorders, breast cancer, vein diseases, osteoporosis, and
tooth decay.

XXY males can have normal sex lives, but they usually make little or no sperm.  Between 95 percent and 99 percent of XXY
males are infertile because their body doesn’t produce sperm.

Language development: As boys, between 25 percent and 85 percent of XXY males have some kind of language problem,
such as learning to talk late, trouble using language to express thoughts and needs, problems reading, and trouble processing
what they hear.

As adults, XXY males may have a harder time doing work that involves reading and writing, but most hold jobs and have
successful careers.  

Social development: As babies, XXY males tend to be quiet and easygoing.  As they get older, they are usually quieter, less
self-confident, less active, and more helpful and obedient than other boys.

As teens, XXY males tend to be quiet and shy. They may struggle in school and sports, meaning they may have more trouble
“fitting in” with other kids.

However, as adults, XXY males live lives similar to men without the condition; they have friends, families, and normal social

Possible Causes of Klinefelter Syndrome/ XXY Condition

No one knows what puts a couple at risk for conceiving an XXY child. Advanced maternal age increases the risk for the XXY
chromosome count, but only slightly. Furthermore, recent studies conducted by NICHD, a geneticist, showed that half the
time, the extra chromosome comes from the father. Researchers explained that cells destined to become sperm or eggs undergo
a process known as meiosis. In this process, the 46 chromosomes in the cell separate, ultimately producing two new cells
having 23 chromosomes each. Before meiosis is completed, however, chromosomes pair with their corresponding
chromosomes and exchange bits of genetic material.

In women, X chromosomes pair; in men, the X and Y chromosome pair. After the exchange, the chromosomes separate, and
meiosis continues. In some cases, the Xs or the X chromosome and Y chromosome fail to pair and fail to exchange genetic
material. Occasionally, this results in their moving independently to the same cell, producing either an egg with two Xs, or a
sperm having both an X and a Y chromosome. When a sperm having both an X and a Y chromosome fertilizes an egg having a
single X chromosome, or a normal Y- bearing sperm fertilizes an egg.

Occasionally, variations of the XXY chromosome count may occur, the most common being the XY/XXY combination. In this
variation, some of the cells in the male's body have an additional X chromosome, and the rest have the normal XY chromosome
count. The percentage of cells containing the extra chromosome varies from case to case. In some instances, XY/XXY
combinations may have enough normally functioning cells in the testes to allow them to father children.

A few instances of males having two or even three additional X chromosomes have also been reported in the medical literature.
In these individuals, the classic features of Klinefelter syndrome may be exaggerated, with low I.Q. or moderate to severe
mental retardation also occurring.

In rare instances, an individual may possess both an additional X and an additional Y chromosome. The medical literature
describes XXYY males as having slight to moderate mental retardation. They may sometimes be aggressive or even violent.
Although they may have a rounded body type and decreased sex drive, experts disagree whether testosterone injections are
appropriate for all of them.

Scientists admit, however, that because these cases are so rare, not much is known about them. Most of the XXYY males who
have been studied were referred to treatment because they were violent and got into trouble with the law. It is not known
whether XXYY males are inherently aggressive by nature, or whether only a few extreme individuals come to the attention of
researchers precisely because they are aggressive.

Finding a Diagnosis for Klinefelter Syndrome/ XXY Condition

Because they often don't appear any different from anyone else, many XXY males probably never learn of their extra
chromosome. However, if they are to be diagnosed, chances are greatest at one of the following times in life: before or shortly
after birth, early childhood, adolescence, and in adulthood (as a result of testing for infertility).

In recent years, many XXY males have been diagnosed before birth, through amniocentesis or chorionic villus sampling (CVS).
In amniocentesis, a sample of the fluid surrounding the fetus is withdrawn. Fetal cells in the fluid are then examined for
chromosomal abnormalities. CVS is similar to amniocentesis, except that the procedure is done in the first trimester, and the
fetal cells needed for examination are taken from the placenta. Neither procedure is used routinely, except when there is a
family history of genetic defects; the pregnant woman is older than 35, or when other medical indications are present.

The next most likely opportunity for diagnosis is when the child begins school. A physician may suspect a boy is an XXY male
if he is delayed in learning to talk and has difficulty with reading and writing. XXY boys may also be tall and thin and somewhat
passive and shy. Again, however, there are no guarantees. Some of the boys who fit this description will have the XXY
chromosome count, but many others will not.

A few XXY males are diagnosed at adolescence, when excessive breast development forces them to seek medical attention.
Like some chromosomally normal males, many XXY males undergo slight breast enlargement at puberty. Of these, only about a
third-10 percent of XXY males in all-will develop breasts large enough to embarrass them.

The final chance for diagnosis is at adulthood, as a result of testing for infertility. At this time, an examining physician may note
the undersized testes characteristic of an XXY male. In addition to infertility tests, the physician may order tests to detect
increased levels of hormones known as gonadotropins, common in XXY males.

A karyotype is used to confirm the diagnosis. In this procedure, a small blood sample is drawn. White blood cells are then
separated from the sample, mixed with tissue culture medium, incubated, and checked for chromosomal abnormalities, such as
an extra X chromosome.

Klinefelter Syndrome / XXY Condition during Childhood

According to Dr. Robinson, the director of the NICHD-funded study, XXY babies differ little from other children their age.
They tend to start life as what many parents call "good" babies-quiet, undemanding, and perhaps even a little passive. As
toddlers, they may be somewhat shy and reserved. They usually learn to walk later than most other children, and may have
similar delays in learning to speak.

In some, the language delays may be more severe, with the child not fully learning to talk until about age 5. Others may learn to
speak at a normal rate, and not meet with any problems until they begin school, where they may experience reading difficulties.
A few may not have any problems at all-in learning to speak or in learning to read.

XXY males usually have difficulty with expressive language the ability to put thoughts, ideas, and emotions into words. In
contrast, their faculty for receptive language-understanding what is said-is close to normal. In addition to academic help, XXY
boys, like other language disabled children, may need help with social skills. Language is essential not only for learning the
school curriculum, but also for building social relationships. By talking and listening, children make friends-in the process,
sharing information, attitudes, and beliefs. Through language, they also learn how to behave-not just in the classroom, but also
on the playground. If their sons' language disability seems to prevent them from fitting in socially, the parents of XXY boys
may want to ask school officials about a social skills training program.

Throughout childhood perhaps, even, for the rest of their lives-XXY boys maintain the same temperament and character they
first displayed as infants and toddlers. As a group, they tend to be shy, somewhat passive, and unlikely to take a leadership role.
Although they do make friends with other children, they tend to have only a few friends at a time. Researchers also describe
them as cooperative and eager to please.

The XXY Boy in the Classroom

Although there are exceptions, XXY boys are usually well behaved in the classroom. Most are shy, quiet, and eager to please
the teacher. But when faced with material they find difficult, they tend to withdraw into quiet daydreaming. Teachers
sometimes fail to realize they have a language problem, and dismiss them as lazy, saying they could do the work if they would
only try. Many become so quiet that teachers forget they're even in the room. As a result, they fall farther and farther behind,
and eventually may be held back a grade.

Education for Children with Klinefelter Syndrome / XXY Boys

XXY boys do best in small, structured classrooms where teachers can give them a lot of individual attention. It’s suggested that
parents who can meet the expense consider sending their sons to a private school offering special educational services.

Parents who cannot afford private schools should become familiar with Public Law 94-142, the Education of the Handicapped
Act, now called the Individuals with Disabilities Education Act. This law, adopted by Congress in 1975, states that all children
with disabilities have a right to a free, appropriate public education. The law cannot ensure that every child who needs special
educational services will automatically get them. But the law does allow parents to take action when they suspect their child has
a learning disability.

Parents may wish to contact their local and state boards of education for information on how the law has been enforced in their
area. In addition, local educational groups may be able to provide useful information on working with school systems. The local
public school system, the state board of education, or local parents groups may be able to tell parents where they find more
resources available in their area.

Services for infants, toddlers and pre-schoolers

The chances for reducing the impact of a learning disability are greatest in early childhood. Public Law is an amendment that
assists states in providing special educational services for infants, toddlers, and preschoolers. Eligibility requirements and
entrance procedures vary from state to state. To learn the agencies to contact in their area, parents may call the Federation for
Children with Special Needs at (800) 331-0688.

Treatments for Klinefelter Syndrome

The XXY chromosome pattern can not be changed. But, there are a variety of ways to treat the symptoms of the XXY

Educational treatments – As children, many XXY males qualify for special services to help them in school. Teachers can
also help by using certain methods in the classroom, such as breaking bigger tasks into small steps.
 Therapeutic options – A variety of therapists, such as physical, speech, occupational, behavioral, mental health, and family
therapists, can often help reduce or eliminate some of the symptoms of the XXY condition, such as poor muscle tone, speech
or language problems, or low self-confidence.
Medical treatments – Testosterone replacement therapy (TRT) can greatly help XXY males get their testosterone levels into
normal range. Having a more normal testosterone level can help develop bigger muscles, deepen the voice, and grow facial and
body hair. TRT often starts when a boy reaches puberty. Some XXY males can also benefit from fertility treatment to help
them father children.

Testosterone Treatment for XXY Males

One of the most important factors for all types of treatment is starting it as early in life as possible. Preferably, XXY males
should begin testosterone treatment as they enter puberty. XXY males diagnosed in adulthood are also likely to benefit from the
hormone. A regular schedule of testosterone injections will increase strength and muscle size, and promote the growth of facial
and body hair.

In addition to these physical changes, testosterone injections often bring on psychological changes as well. As they begin to
develop a more masculine appearance, the self-confidence of XXY males tends to increase. Many become more energetic and
stop having sudden, angry changes in moods. What is not clear is whether these psychological changes are a direct result of
testosterone treatment or are a side benefit of the increased self confidence that the treatment may bring. As a group, XXY
boys tend to suffer from depression, mainly because of their academic difficulties and problems fitting in with other males their
age. Sudden, angry changes in mood are typical of depressed people.

Other benefits of testosterone treatment may include decreased need for sleep, an enhanced ability to concentrate, and improved
relations with others. But to obtain these benefits an XXY male must decide, on his own, that he is ready to continue a regular
schedule of injections. Sometimes, younger adolescents, who may be somewhat immature, seem not quite ready to take the
shots. It is an inconvenience, and many don't like needles. Most physicians do not push the young-men to take the injections.
Instead, they usually recommend informing XXY adolescents and their parents about the benefits of testosterone injections and
letting them take as much time as they need to make their decision.

Individuals may respond to testosterone treatment in different ways. Although the majority of XXY males ultimately will benefit
from testosterone, a few will not. To ensure that the injections will provide the maximum benefit, XXY males who are ready to
begin testosterone injections should consult a qualified endocrinologist (a specialist in hormonal interactions) who has
experience treating XXY males.
Side effects of the injections are few. Some individuals may develop a minor allergic reaction at the injection site, resulting in an
itchy welt resembling a mosquito bite. Applying a non-prescription hydrocortisone cream to the area will reduce swelling and

In addition, testosterone injections may result in a condition known as benign prostatic hyperplasia (BPH). This condition is
common in chromosomally normal males as well, affecting more than 50 percent of men in their sixties, and as many as 90
percent in their seventies and eighties. In XXY males receiving testosterone injections, this condition may begin sometime after
age 40.

The prostate is a small gland about the size of a walnut, which helps to manufacture semen. The gland is located just beneath
the bladder and surrounds the urethra, the tube through which urine passes out of the body. In BPH, the prostate increases in
size, sometimes squeezing the bladder and urethra and causing difficulty urinating, "dribbling" after urination, and the need to
urinate frequently.

XXY males receiving testosterone injections should consult their physicians about a regular schedule of prostate examinations.
BPH can often be detected early by a rectal exam. If the prostate greatly interferes with the flow of urine, excess prostate tissue
can be trimmed away by a surgical instrument that is inserted in the penis, through the urethra.

Health Considerations in XXY Males

Compared with other males, XXY males have a slightly increased risk of autoimmune disorders. In this group of diseases, the
immune system, for unknown reasons, attacks the body's organs or tissues. The most well known of these diseases are type I
(insulin dependent) diabetes, autoimmune thyroiditis, and lupus erythematosus. Most of these conditions can be treated with

XXY males with enlarged breasts have the same risk of breast cancer as do women-roughly 50 times the risk XY males have.
For this reason, these XXY adolescents and men need to practice regular breast self examination. XXY males may also wish to
consult their physicians about the need for more thorough breast examinations by medical professionals.

In addition, XXY males who do not receive testosterone injections may have an increased risk of developing osteoporosis in
later life. In this condition, which usually afflicts women after the age of menopause, the bones lose calcium, becoming brittle
and more likely to break.