Harry Klinefelter

  • Klinefelter's Syndrome is a genetic disorder first discoverd by Harry Klinefelter in 1942. (everything2.com)
  • Klinefelter's Syndrome (KS), was first described by Dr. Harry Klinefelter and his colleagues in 1942, while studying nine men with fertility problems and enlarged breasts. (medindia.net)
  • It is named after Harry Klinefelter who identified the condition in the 1940s. (wikipedia.org)
  • It was first described in 1942 by Dr. Harry Klinefelter. (pediatriceducation.org)
  • The group of symptoms with Klinefelter Syndrome was first described in 1942 by Dr. Harry Klinefelter and his coworkers. (blogspot.com)


  • Instead of one X and one Y chromosome like most guys have, guys with Klinefelter syndrome are born with an extra "X" chromosome in most or all of their cells. (kidshealth.org)
  • If only some cells have the extra X chromosome, it's called mosaic Klinefelter syndrome . (kidshealth.org)
  • Variants of the syndrome are characterized by more than one extra X chromosome, e.g., 48,XXXY. (everything2.com)
  • Wikstrom AM, Painter JN, Raivio T, Aittomaki K, Dunkel L. Genetic features of the X chromosome affect pubertal development and testicular degeneration in adolescent boys with Klinefelter syndrome. (medscape.com)
  • Klinefelter's Syndrome, which affects 1 in 500 to 1 in 1000 live births, is a sex chromosomal genetic disorder where the affected males have an extra X chromosome. (medindia.net)
  • Although most patients with Klinefelter's Syndrome have only one extra X chromosome in their cells, approximately 10% of the patients have different forms of the disorder. (medindia.net)
  • In a small proportion of the Klinefelter individuals, a few of the body cells may be normal while the others may have an additional X chromosome. (medindia.net)
  • Klinefelter s Syndrome is caused by the presence of an additional X chromosome. (medindia.net)
  • Klinefelter syndrome is a condition that occurs in men as a result of an extra X chromosome. (genome.gov)
  • This study will elucidate how the parental origin of the X-chromosome influences health status as well as metabolic fate in Klinefelter patients. (clinicaltrials.gov)
  • Klinefelter syndrome (KS) is one of the most common sex-chromosome disorders as it affects up to 1 in every 600-1000 newborn males. (medsci.org)
  • Klinefelter syndrome is characterized by the presence of an extra (one or more) X chromosome in male individuals, giving a 47,XXY rather than 46,XY karyotype. (neurologyadvisor.com)
  • Variants of Klinefelter syndrome can include three or more copies of the X chromosome and are typically more severe. (neurologyadvisor.com)
  • Mosaic Klinefelter syndrome occurs in the presence of a normal cell line and a cell line with an extra X chromosome (47,XY/47,XXY). (neurologyadvisor.com)
  • Males with variants of Klinefelter syndrome with increased copies of the X chromosome (48,XXXY, 48,XXYY, 49,XXXXY, and so on) typically have a more severe presentation than do those with 47,XXY, because of the presence of more X chromosome material. (neurologyadvisor.com)
  • Klinefelter syndrome is caused by the presence of an extra X chromosome in every cell of the body (47,XXY) in a male individual. (neurologyadvisor.com)
  • A karyotype, or chromosome analysis, should be ordered if Klinefelter syndrome is suspected. (neurologyadvisor.com)
  • One of the most common genetic conditions that affect males is klinefelter syndrome, which is usually the result of an extra copy of the X chromosome in each cell. (epharmapedia.com)
  • When an extra sex chromosome is inherited from one of the parents during the formation of the embryo, Klinefelter syndrome occurs, which happens entirely by chance because it is a random occurrence. (epharmapedia.com)
  • Most males with Klinefelter syndrome have one extra copy of the X chromosome in each cell. (blogspot.com)
  • Variants of Klinefelter syndrome involve more than one extra X chromosome or extra copies of both the X and Y chromosomes in each cell. (blogspot.com)
  • Unraveling unusual X-chromosome patterns during fragile-X syndrome genetic testing. (readbyqxmd.com)
  • Klinefelter's syndrome is a genetic condition whereby an additional X chromosome is found. (blogspot.com)
  • Males with Klinefelter syndrome, who have an extra X chromosome, will also undergo X inactivation to have only one completely active X chromosome. (wikipedia.org)
  • Turner Syndrome is a result from one of female sex chromosome abnormalities. (wikipedia.org)
  • Triple-X Syndrome is another syndrome that occurs from a female sex chromosome abnormality. (wikipedia.org)
  • Klinefelter Syndrome is a syndrome resulting from a male sex chromosome abnormality. (wikipedia.org)
  • XYY Syndrome is also a syndrome resulting from a male sex chromosome abnormality. (wikipedia.org)
  • Initially he suspected this to be endocrine disorder and postulated the presence of a second testicular hormone, but in 1959, Patricia A. Jacobs and Dr. J.A. Strong (Western General Hospital and University of Edinburg) demonstrated that a male patient with the phenotype of Klinefelter syndrome had an additional X chromosome (46 XXY). (wikipedia.org)
  • this quote needs a citation] On the later discovery of the extra X chromosome: Fourteen years after the original description of the syndrome, 2 groups independently discovered that the buccal mucosal cells of these patients contained an extra chromatin mass, or were chromatin positive. (wikipedia.org)
  • The film's title appears to be a reference to Klinefelter syndrome, a condition in which individuals have an extra X sex chromosome. (wikipedia.org)
  • He has Klinefelter's syndrome (a supplemental X chromosome). (wikipedia.org)
  • Age (see also: Paternal age effect) Genetic defects on the Y chromosome Y chromosome microdeletions Abnormal set of chromosomes Klinefelter syndrome Centriole Neoplasm, e.g. seminoma Idiopathic failure Cryptorchidism Trauma Hydrocele Mumps Malaria Testicular cancer Defects in USP26 in some cases Acrosomal defects affecting egg penetration Idiopathic oligospermia - unexplained sperm deficiencies account for 30% of male infertility. (wikipedia.org)


  • What is Klinefelter's Syndrome? (everything2.com)
  • Symptoms of Klinefelter's Syndrome include: occasional breast enlargement, a lack of facial and/or body hair , a rounded body type, and infertility . (everything2.com)
  • Klinefelter's Syndrome is not fatal and cannot be cured , however, the effects can be lessened with testosterone injections starting anytime after the onset of puberty . (everything2.com)
  • Klinefelter's Syndrome is diagnosed in about 1 in 500 to 1 in 1000 men. (everything2.com)
  • Damani MN, Mittal R, Oates RD. Testicular tissue extraction in a young male with 47,XXY Klinefelter's syndrome: potential strategy for preservation of fertility. (medscape.com)
  • Successful fertility treatment for Klinefelter's syndrome. (medscape.com)
  • The clinical significance of bone mineral density and testosterone levels in Korean men with non-mosaic Klinefelter's syndrome. (medscape.com)
  • Rovenský J. Rheumatic diseases and Klinefelter's syndrome. (medscape.com)
  • Klinefelter's Syndrome (KS) is a sex chromosomal disorder like Turner s syndrome. (medindia.net)
  • What are the Causes of Klinefelter's Syndrome? (medindia.net)
  • What are the Signs and Symptoms Klinefelter's Syndrome? (medindia.net)
  • Objective To investigate the criminal pattern in men between 15 and 70 years of age diagnosed with 47,XXY (Klinefelter's syndrome (KS)) or 47,XYY compared to the general population. (bmj.com)
  • Corrigendum to "Klinefelter's syndrome (47,XXY) is in excess among men with Sjögren's syndrome" [Clin. (readbyqxmd.com)
  • Klinefelter's Syndrome: Understanding Klinefelter's syndrome in simple terms. (blogspot.com)
  • Syndromes associated with mediastinal germ cell tumors include Hematologic Neoplasia and Klinefelter's syndrome. (wikipedia.org)
  • As someone with untreated Klinefelter's syndrome, Heaulme was at the time incapable of committing rape in the "standard" manner. (wikipedia.org)
  • Renard was diagnosed with Klinefelter's syndrome, having 47 chromosones (XXY). (wikipedia.org)

variants of Klinefelter syndrome

  • In addition to affecting male sexual development, variants of Klinefelter syndrome are associated with intellectual disability, distinctive facial features, skeletal abnormalities, poor coordination, and severe problems with speech. (blogspot.com)

Adults With Klinefelter Syndrome

  • Older children and adults with Klinefelter syndrome tend to be taller than other males their age. (blogspot.com)
  • Little is known about adults with Klinefelter Syndrome. (blogspot.com)

association with Klinefelter syndrome


  • What Are the Signs & Symptoms of Klinefelter Syndrome? (kidshealth.org)
  • Males who have Klinefelter syndrome may have the following symptoms: small, firm testes, a small penis, sparse pubic, armpit and facial hair, enlarged breasts (called gynecomastia), tall stature, and abnormal body proportions (long legs, short trunk). (genome.gov)
  • Klinefelter syndrome (KS) also known as 47,XXY or XXY, is the set of symptoms that result from two or more X chromosomes in males. (wikipedia.org)
  • The signs and symptoms of this syndrome vary. (epharmapedia.com)
  • Most of the time, this condition goes undiagnosed until adulthood, and many people with this syndrome have only a few noticeable symptoms. (epharmapedia.com)
  • These conditions tend to have more severe signs and symptoms than classic Klinefelter syndrome. (blogspot.com)
  • The widelyvariable phenotypic spectrum and the different severity of symptoms in men with Klinefelter syndrome (KS) suggest a role for epigenetic mediators. (readbyqxmd.com)
  • Those affected with Klinefelter syndrome often do not show highly-visible symptoms and are not aware of their condition, unless diagnosed later in life (usually due to infertility). (wikipedia.org)

Males with Klinefelter

  • Males with Klinefelter syndrome typically have low testosterone levels, causing sparse body hair, decreased muscle mass, small testes and penis, feminized body habitus, and decreased libido. (neurologyadvisor.com)
  • Compared with other men, adult males with Klinefelter syndrome have an increased risk of developing breast cancer and a chronic inflammatory disease called systemic lupus erythematosus. (blogspot.com)


  • Klinefelter syndrome (KS) is the most frequent form of male hypogonadism. (mysciencework.com)
  • An example of a hypogonadism resulting from the lack of hormone response is androgen insensitivity syndrome, where there are inadequate receptors to bind the testosterone, resulting in a female appearance despite XY chromosomes. (wikipedia.org)
  • Polycystic ovary syndrome, and Kallmann syndrome, also called hypogonadotropic hypogonadism. (wikipedia.org)
  • Examples of congenital causes of hypogonadism, that is, causes that are present at birth: Turner syndrome in females, and Klinefelter syndrome in males. (wikipedia.org)
  • Examples of hypogonadism that affect fertility more than hormone production are Klinefelter syndrome and Kartagener syndrome. (wikipedia.org)


  • Genetic variation in Klinefelter individuals show three to four extra X chromosomes, extra Y-chromosomes or mosaics . (medindia.net)
  • Klinefelter s Syndrome occurs as the result of an error during the formation of an egg or a sperm that results in a person having a XXY combination or 47 chromosomes instead of the normal 46. (medindia.net)
  • In humans, the most common sex chromosomal disorder is Klinefelter syndrome (KS), caused by the presence of one or more extra X-chromosomes. (readbyqxmd.com)


  • Klinefelter syndrome usually occurs randomly. (wikipedia.org)
  • Klinefelter syndrome occurs in 1/500-1000 live births and is the most common chromosomal cause of male infertility. (neurologyadvisor.com)
  • Female individuals with an autosomal dominant or recessive form can also be affected, whereas Klinefelter syndrome occurs only in male patients. (neurologyadvisor.com)

testosterone levels

  • Sometimes, weaker bones, lower energy levels and gynecomastia may be caused due to the low testosterone levels caused by klinefelter syndrome. (epharmapedia.com)


  • Noonan syndrome, Turner syndrome (45X,0), Klinefelter syndrome (47XXY), XY females with SRY gene-immunity Secondary - defect lies outside of the gonad: e.g. (wikipedia.org)


  • The primary lymphedema can also be a part of more complex malformative diseases such as Klinefelter, Turner or Noonan syndromes. (readbyqxmd.com)


  • When puberty starts and guys' bodies begin to make sex hormones, boys with Klinefelter usually don't produce as much of the male hormone testosterone. (kidshealth.org)
  • Starting testosterone therapy at the time of the usual onset of puberty could be helpful in treating or preventing a number of problems caused by Klinefelter syndrome. (epharmapedia.com)
  • If given estrogen replacement therapy around the age of puberty, women with Turner syndrome appear relatively normal. (wikipedia.org)


  • These include Kallmann syndrome and 46,XX karyotype (in males). (medscape.com)


  • The physical findings in patients with Klinefelter syndrome vary. (medscape.com)
  • It's not all about the testes: medical issues in Klinefelter patients. (medscape.com)
  • These will be related to clinically relevant metabolic and inflammatory patterns as well as fertility to identify individual risks as well as treatment strategies for Klinefelter patients. (clinicaltrials.gov)
  • In Klinefelter Syndrome Patients, What are the Common Behavioral Problems? (pediatriceducation.org)
  • this quote needs a citation] Klinefelter comments on gynecomastia: A few years after the syndrome was described, Heller and Nelson reported that the gynecomastia was not a necessary part of the syndrome, though it occurred in about 75% of the patients. (wikipedia.org)


  • Mosaic Klinefelter syndrome can have a milder presentation (such as the presence of fertility), depending on the number of cells in the body with the extra X and where those cells are located. (neurologyadvisor.com)


  • Examples include Klinefelter syndrome and Turner syndrome. (wikipedia.org)


  • What Causes Klinefelter Syndrome? (kidshealth.org)
  • The pathologic causes of gynecomastia are diverse and may include Klinefelter syndrome, certain cancers, endocrine disorders, metabolic dysfunction, various medications, or may occur due to a natural decline in testosterone production. (wikipedia.org)


  • Close S, Fennoy I, Smaldone A, Reame N. Phenotype and Adverse Quality of Life in Boys with Klinefelter Syndrome. (medscape.com)

genetic diseases

  • Klinefelter syndrome isn't passed down through families like some genetic diseases . (kidshealth.org)


  • Although infertility could be caused by something other than this syndrome, however, men are not diagnosed with this condition until they realize that they are not able to father a child. (epharmapedia.com)


  • They also have higher rates of diabetes mellitus, obesity, metabolic syndrome, osteopenia/osteoporosis and autoimmune disorders especially systemic lupus erythematosus. (pediatriceducation.org)


  • Klinefelter syndrome is one of the most common chromosomal disorders, occurring in 1:500 to 1:1,000 live male births. (wikipedia.org)
  • A 17-year-old male with known Klinefelter syndrome (KS) came to clinic for his health supervision visit. (pediatriceducation.org)
  • The diagnosis of a healthy male with Klinefelter syndrome was made. (pediatriceducation.org)
  • Klinefelter syndrome (KS) is a common genetic abnormaly with a prevalence of 1 in ~650 male births. (pediatriceducation.org)
  • Klinefelter syndrome is a chromosomal condition that affects male sexual development. (blogspot.com)
  • A small proportion of male gynecomastia cases may be seen with rare inherited disorders such as spinal and bulbar muscular atrophy and the very rare aromatase excess syndrome. (wikipedia.org)


  • In terms of the child's education, XXY's with Klinefelter Syndrome are typically well behaved in the classroom and are eager to please the teacher. (blogspot.com)


  • The onset of adolescence in Klinefelter s Syndrome is marked by the lack of testosterone, poor growth of secondary sexual characters, gynecomastia and sterility. (medindia.net)
  • In some cases, this syndrome could cause learning and social difficulties during childhood and adolescence. (epharmapedia.com)


  • The role of genes, intelligence, personality, and social engagement in cognitive performance in Klinefelter syndrome. (medscape.com)
  • The syndrome is also related to a wide range of cognitive deficits, among which language-based learning disabilities and verbal cognition impairment are frequently diagnosed. (medsci.org)


  • Klinefelter described his findings as follows: I first worked under Dr. Howard Means, measuring oxygen consumption of adrenal gland slices in the Warburg apparatus, but I was so unsuccessful at it, breaking most of the apparatus, that in September, I asked Dr. Means if I might work with Dr. Fuller Albright, since I primarily wanted to learn some clinical endocrinology. (wikipedia.org)


  • This syndrome could cause boys and teenagers to be taller and have longer legs than others. (epharmapedia.com)
  • Although men with klinefelter syndrome may be taller than average, otherwise they are normal in appearance. (epharmapedia.com)

sexual characteristics

  • Those with 47,XXYY may have mild mental retardation in addition to the sexual characteristics of Klinefelter syndrome. (neurologyadvisor.com)


  • Klinefelter syndrome is associated with an increased risk for breast cancer, a rare tumor called extragonadal germ cell tumor, lung disease, varicose veins and osteoporosis. (genome.gov)


  • XXY boys with Klinefelter Syndrome tend not to be as strong or as athletic as other boys. (blogspot.com)

affects males


  • Differences in boys with Klinefelter syndrome can range from mild to severe. (kidshealth.org)


  • Kallman syndrome, characterized by gonadotropin-releasing hormone deficiency and anosmia, has several characteristics similar to those of Klinefelter syndrome, but it is much rarer. (neurologyadvisor.com)
  • Although rarer, some primaries lymphedemas are family forms such the syndromes of Milroy and Meige. (readbyqxmd.com)


  • Boys with Klinefelter syndrome may also have problems with attention, speech development, and learning word skills like spelling, reading, or writing. (kidshealth.org)
  • Boys with Klinefelter syndrome may have difficulty with spelling, reading, writing, and paying attention. (kidshealth.org)
  • Some boys with Klinefelter syndrome are less interested in sports or physical activities. (kidshealth.org)
  • Boys who are born with this syndrome have low levels of the sex hormone testosterone because this condition could affect testicular growth, which could result in reduced muscle growth, gynecomastia (enlarged breast tissue) and reduced body and facial hair. (epharmapedia.com)
  • Boys with this syndrome may be less assertive than others, and they may be shy. (epharmapedia.com)
  • Boys with Klinefelter syndrome may have learning disabilities and difficulty with speech and language development. (blogspot.com)


  • Men who have Klinefelter syndrome also have an increased risk for autoimmune disorders such as lupus, rheumatoid arthritis and Sjogren's syndrome. (genome.gov)
  • Individuals with Klinefelter syndrome are at an increased risk for breast cancer, autoimmune diseases, diabetes, osteoporosis, and deep vein thrombosis. (neurologyadvisor.com)


  • These individuals are also referred to as 'males with XXY syndrome' , or as 'XXY males' . (medindia.net)


  • Most often, Klinefelter syndrome is the result of one extra X (written as XXY). (genome.gov)


  • For example, guys with Klinefelter syndrome may be more likely to get some types of cancer and other diseases, like type 2 diabetes and osteoporosis, a condition where the bones become weaker later in life. (kidshealth.org)
  • It is known as the forgotten syndrome, as it is a common yet under-diagnosed genetic condition, despite being described almost 70 years ago. (medindia.net)
  • Although a person will still need treatment for the condition, however, he probably won't have children in case he has Klinefelter syndrome. (epharmapedia.com)


  • Doctors think Klinefelter syndrome is fairly common. (kidshealth.org)
  • The Klinefelter Syndrome is one of the most common genetic disorders in men. (clinicaltrials.gov)
  • The patient had earlier noted that he wanted to go to college after high school and the resident said that it was very common for people with Klinefelter syndrome to have some academic problems and maybe the patient would benefit from formal testing so that he could get the appropriate help for school and college. (pediatriceducation.org)


  • Klinefelter HF Jr, Reifenstein EC Jr, Albright F. Syndrome characterized by gynecomastia aspermatogenesis without a-Leydigism and increased excretion of follicle-stimulating hormone. (medscape.com)
  • under the supervision of Fuller Albright he described a group of nine men with "gynecomastia, aspermatogenesis without aleydigism, and increased excretion of follicle-stimulating hormone", the first description of what would be called the Klinefelter syndrome. (wikipedia.org)
  • The title, "A Syndrome Characterized by Gynecomastia, Aspermatogenesis without Aleydigism, and Increased Excretion of Follicle-Stimulating Hormone," was so long that the syndrome came to be known by my name, though it was really just another of Dr. Albright's diseases. (wikipedia.org)
  • Medications such as aromatase inhibitors have been found to be effective in rare cases of gynecomastia from disorders such as aromatase excess syndrome or Peutz-Jeghers syndrome, but surgical removal of the excess tissue is usually required. (wikipedia.org)



  • Other manifestations of Kallman syndrome can include digital abnormalities, renal agenesis, sensorineural hearing loss, cleft lip/palate, and/or agenesis of the corpus callosum. (neurologyadvisor.com)
  • Examples of hypothalamic defects include Kallmann syndrome. (wikipedia.org)


  • Most men who have Klinefelter syndrome can expect to have a normal and productive life. (genome.gov)


  • Women who are 35 and older have the greatest risk of having children with Klinefelter s syndrome. (medindia.net)
  • Most men who have Klinefelter syndrome are not able to father children. (genome.gov)
  • Although new procedures are making it possible for men with this syndrome to father children, however, most men with Klinedelter syndrome are infertile. (epharmapedia.com)
  • As many children with Klinefelter Syndrome have speech and language difficulties, it may also be helpful to work with a speech pathologist. (blogspot.com)


  • This syndrome may not show any noticeable signs and syndromes at first. (epharmapedia.com)
  • It is also one of the signs of CHARGE syndrome. (wikipedia.org)