Between 1 in 500 and 1 in 1,000 boys are born with Klinefelter's syndrome (KS). Klinefelter syndrome is the most common sex chromosome disorder, manifested as hypogonadism, gynecomastia, and impaired spermatogenesis. It is characterized by the presence of one or more extra X chromosomes. Klinefelter syndrome may adversely affect testicular growth, resulting in smaller than normal testicles, which can lead to lower production of testosterone. Klinefelter’s syndrome is the clinical result of an additional X chromosome in males (47,XXY), although other chromosome abnormalities (such as 46,XY/47,XXY mosaicism; 48,XXXY; 49,XXXXY) account for 10-20% of cases.1 2 Classic clinical findings include infertility, small testes, hypergonadotropic hypogonadism (elevated luteinising hormone and follicular stimulating hormone … Klinefelter Syndrome. 2002;61:49–53. Learn more about the causes, symptoms, and treatment of Klinefelter syndrome. It can affect physical and mental development. We offer support and information to all affected by, or having an interest in, Klinefelter’s Syndrome. Early recognition and hormonal treatment can improve quality of life and prevent serious complications. This may have implications for treatment of Klinefelter's syndrome and suggests that the X chromosome may be involved in the … XXY aneuploidy is the most common disorder of sex chromosomes in humans, with prevalence of one in 500 males. A mother who gives birth over the age of 40 is two to three times more likely to have a baby with Klinefelter syndrome than a mother who is age 30 at birth. Those affected … Chromosomes are genetic material and males typically have one X and one Y chromosome (XY) and females have two X chromosomes (XX). Next Article Klinefelter's syndrome: a late diagnosis. Until now, however, … Klinefelter's syndrome is the most common cause of testicular failure that results in impairments in both spermatogenesis and—to a lesser extent—testosterone production. It causes hypogonadism and infertility. Early identification is helpful in treating and managing Klinefelter syndrome. There are 2 types of chromosome, called the sex chromosomes, that determine the genetic sex of a baby. Klinefelter syndrome is the most frequent sex chromosome abnormality and is seen in about 150 boys out of every 100,000 live-born boys. Klinefelter syndrome is largely undiagnosed in the general population. Klinefelter syndrome (sometimes called Klinefelter's, KS or XXY) is where boys and men are born with an extra X chromosome. Patients with Klinefelter syndrome are highly susceptible to psychiatric disturbances as compared to the general population. Affected males have an extra X chromosome. Signs and symptoms vary greatly. It results in small testes, testosterone deficiency, infertility and often in swelling of glandular breast tissue (gynecomastia). … Treatment may include: Testosterone replacement: About half of people with … Klinefelter Syndrome affects 1 in 500 male conceptions and is therefore the most common sex chromosome abnormality. Klinefelter's syndrome is a genetic condition that only affects males. Testosterone replacement therapy is a mainstay of treatment. They are written by UK doctors and based on research evidence, UK and European Guidelines. Klinefelter syndrome occurs when a male receives an extra X sex chromosome. This results in smaller-sized testicles, low testosterone levels, and possibly infertility. It is characterized by the presence of one or more extra X chromosomes. National Helpline 0300 111 47 48 WebAdmin@ksa-uk.net. Humans normally have two sex chromosomes in each cell—females have two X chromosomes (described as XX), and males have one X and one Y chromosome (described as XY). Patients with Klinefelter syndrome are highly susceptible to psychiatric disturbances as compared to the general population. With an incidence of 0.1% to 0.2% of male neonates (i.e. Symptoms. Klinefelter syndrome (KS) is the most common genetic form of male hypogonadism, but overt phenotype becomes evident only after puberty. Klinefelter syndrome (KS) is the result of 2 or more X chromosomes in a phenotypic male. REVIEW ARTICLE Klinefelter Syndrome The Commonest Form of Hypogonadism, but Often Overlooked or Untreated Eberhard Nieschlag SUMMARY Background: Klinefelter syndrome (KS) with the karyotype 47,XXY is one of the commonest types of congenital chro-mosomal disorder in males, with an incidence of 0.1% to 0.2% of newborn male infants. Klinefelter syndrome (KS) is the result of 2 or more X chromosomes in a phenotypic male. Women who get pregnant after age 35 are slightly more likely to have a boy with this syndrome than younger women. 54 In early life, Klinefelter may be diagnosed in boys with behavioral disorders, abnormally small testes, and long legs (Fig. These include personality changes, depression, … Recent Articles. Here, we report high levels of schizophrenia-spectrum pathology in 32 men with this syndrome in comparison with 26 healthy controls. Klinefelter syndrome can cause problems with learning and sexual development in guys. However, Klinefelter syndrome is often overlooked or untreated. Complications. The clinical phenotype of KS was first described in males with tall stature, small testes, gynecomastia, and azoospermia with the genetic etiology of supernumerary X chromosomes identified in 1959. Klinefelter syndrome only affects males. It is sometimes just called XXY. The classic form (nonmosaic type) of Klinefelter syndrome (KS) is observed in one per 660 births, with up to 3%‐4% occurring in infertile men and 10%‐12% occurring in nonobstructive azoospermia (NOA). Many people with KS are not diagnosed until they are adults, and it is believed that up to two thirds may never be diagnosed at all. Klinefelter's syndrome, characterised by a 47, XXY chromosomal pattern, has largely been associated with physical abnormalities. Often, symptoms are subtle and subjects do not realize they are affected. Chromosomes are packages of genes found in every cell in the body. Klinefelter syndrome 47,XXY was first described 70 years ago (1). Klinefelter syndrome appears to occur more frequently with both older maternal and paternal age (over the age of 35.) You may find the Klinefelter's Syndrome article more useful, or one of our other health articles. Infertility is the most common symptom of Klinefelter syndrome. 16.7). Klinefelter syndrome is the most common sex chromosome disorder, manifested as hypogonadism, gynecomastia, and impaired spermatogenesis. An interesting XXY story from Glass magazine; Research into men’s experience of pregnancy following fertility treatment; Guy’s Hospital First Klinefelter’s Syndrome (KS/XXY) Adolescent Clinic; Contact the KSA . It results from an unequal sharing of sex chromosomes soon after fertilization. report the findings of a survey of the current practices of fertility care in adolescent males with Klinefelter syndrome (KS) among members of the Society for the Study of Male Reproduction, the Pediatric Endocrine Society, and the Endocrine Society (overall response rates of 4.7%, 5%, and 1%, respectively). The primary features are infertility and small poorly functioning testicles. Klinefelter syndrome (KS), also known as 47,XXY is the set of symptoms that result from two or more X chromosomes in males. A study on the KS prevalence in Japan found a lower prevalence at 60 per 100 000, 2 indicating the presence of racial differences. Klinefelter's syndrome is the most common genetic cause of human male infertility, but many cases remain undiagnosed because of substantial variation in clinical presentation and insufficient professional awareness of the syndrome itself. This syndrome is the most common sexchromosome disorder affecting 1 in 500 men across all ethnic groups, but the diagnosis is often delayed because of substantial variation in clinical presentation. Because symptoms of Klinefelter syndrome (KS) can sometimes be very mild, many people are never diagnosed or treated. Klinefelter syndrome is a genetic condition that results when a boy is born with an extra copy of the X chromosome. Klinefelter’s Syndrome (KS) is a common congenital condition which is found in around 1 in 600 live male births and is caused by the presence of one or more additional sex chromosomes. Signs and symptoms seen in Klinefelter syndrome. increased incidence of male breast malignancy; increased incidence of germ cell … These are named either X or Y. Klinefelter syndrome, also known as XXY syndrome, is a condition in boys and men that’s caused by an extra X chromosome. Other sex chromosomal aneuploidies have also been described, although they are much less frequent, with … Klinefelter syndrome, disorder of the human sex chromosomes that occurs in males, one of the most frequent chromosomal disorders in males. Klinefelter syndrome happens when a male is born with an additional X chromosome. Klinefelter syndrome is a genetic condition affecting males, and it often isn't diagnosed until adulthood. Article Translations: What Is Klinefelter Syndrome? Disturbances as compared to the general population we report high levels klinefelter syndrome article schizophrenia-spectrum pathology 32! Sometimes called klinefelter 's, KS or XXY ) is where boys and men are born it! 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