Klinefelter syndrome is one of the most common chromosome conditions in newborns. However, as adults, XXY males live lives similar to men without the condition; they have friends, families, and normal social relationships. XXYY syndrome; Other names: 48,XXYY Klinefelter syndrome: XXYY syndrome: XXYY syndrome is a sex chromosome anomaly in which males have an extra X and Y chromosome. About Klinefelter syndrome. Accessed Sept. 10, 2019. Human cells usually contain two sex chromosomes, one from the mother and one from the father. Accessed Aug. 9, 2019. The XXY condition can affect three main areas of development 1) physical, 2) language, and 3) social. Edwards syndrome is a genetic disorder, in which a person has a third copy of material from chromosome 18, instead of the usual two copies. MedicineNet does not provide medical advice, diagnosis or treatment. Signs and symptoms of Klinefelter syndrome vary widely among males with the disorder. The condition may go undiagnosed until adulthood or it may never be diagnosed. Signs and symptoms of Klinefelter syndrome also vary by age. 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. https://ghr.nlm.nih.gov/condition/klinefelter-syndrome. Symptoms. Mayo Clinic; 2019. Most commonly, affected individuals are taller than average are unable to father biological children (infertile); however the signs and symptoms of Klinefelter syndrome vary among boys and men with this condition. Mayo Clinic facts about coronavirus disease 2019 (COVID-19), Our COVID-19 patient and visitor guidelines, plus trusted health information, Mayo Clinic Health System patient vaccination updates, Mayo Clinic Graduate School of Biomedical Sciences, Mayo Clinic School of Continuous Professional Development, Mayo Clinic School of Graduate Medical Education, Book: Mayo Clinic Family Health Book, 5th Edition, Newsletter: Mayo Clinic Health Letter — Digital Edition, FREE book offer – Mayo Clinic Health Letter, New Year Special -  40% off – Mayo Clinic Diet Online. This site complies with the HONcode standard for trustworthy health information: verify here. This is a genetic abnormality which occurs in males mostly. 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. Endocrine aspects of Klinefelter syndrome. Even though all men with Klinefelter syndrome have the extra X chromosome, not every XXY male has all of those symptoms. Klinefelter syndrome stems from a random genetic event. Humans have 46 chromosomes, including two sex chromosomes that determine a person's sex. Many boys with Klinefelter syndrome — also known as XXY syndrome — have no signs or symptoms, and some don't even know they have it until later in life. Most XXY males are infertile because their bodies don't make a lot of sperm. (This can include being too tall, having long legs and a short trunk and the shoulders being equal to hips in size rather than wider, which is more typical in a male.) Not all males with the condition have the same symptoms or to the same degree. Symptoms of Poly-X KS 11. Extra copies of genes on the X chromosome can interfere with male sexual development and fertility. Often, symptoms are subtle and subjects do not realize they are affected. See also disease and sickness. Mayo Clinic Laboratories. Klinefelter syndrome. This content does not have an English version. 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). Down Syndrome Causes and Symptoms. Wick MJ (expert opinion). Terms of Use. Symptoms of Klinefelter syndrome. See additional information. Latest on COVID-19 vaccination by site: Slow motor development — taking longer than average to sit up, crawl and walk, Problems at birth, such as testicles that haven't descended into the scrotum, Longer legs, shorter torso and broader hips compared with other boys, After puberty, less muscle and less facial and body hair compared with other teens, Difficulty expressing thoughts and feelings or socializing, Problems with reading, writing, spelling or math, One extra copy of the X chromosome in each cell (XXY), the most common cause, An extra X chromosome in some of the cells (mosaic Klinefelter syndrome), with fewer symptoms, More than one extra copy of the X chromosome, which is rare and results in a severe form, Social, emotional and behavioral problems, such as low self-esteem, emotional immaturity and impulsiveness, Infertility and problems with sexual function, Metabolic syndrome, which includes type 2 diabetes, high blood pressure (hypertension), and high cholesterol and triglycerides (hyperlipidemia), Autoimmune disorders such as lupus and rheumatoid arthritis, Tooth and oral problems that make dental cavities more likely. Elsevier; 2020. https://www.clinicalkey.com. The condition may go undiagnosed until adulthood or it may never be diagnosed. 2 It is especially helpful to begin treatment by early puberty. ©1996-2021 MedicineNet, Inc. All rights reserved. Mayo Clinic does not endorse companies or products. They may sit up, crawl, and walk later than other infants. 2019; doi:10.12688/f1000research.16747.1. This can be due to a congenital disorder such as Klinefelter’s syndrome, or acquired as a result of radiation treatment, chemotherapy, mumps, tumors … In childhood, they may also have seizures, crossed eyes, constipation, and recurrent ear infections. What are the treatments for the XXY condition? As they get older, they are usually quieter, less self-confident, less active, and more helpful and obedient than other boys. https://www.nichd.nih.gov/health/topics/klinefelter. Males have an X and a Y sex chromosome (XY). Possible features, which are not always present, may include: Most babies with Klinefelter syndrome do not have noticeable symptoms. Symptoms. Many boys and men do not realise they have it. Females have two X sex chromosomes (XX). Klinefelter syndrome. Down syndrome is a genetic disorder in which, most often, a third copy of chromosome 21 is present in cells because of an abnormal cell division when the egg and sperm first meet. Accessed Aug. 9, 2019. Klinefelter syndrome may increase the risk of: A number of complications caused by Klinefelter syndrome are related to low testosterone (hypogonadism). syndrome [sin´drōm] a combination of symptoms resulting from a single cause or so commonly occurring together as to constitute a distinct clinical picture. As boys, it is not uncommon for 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. XXY males can have normal sex lives, but they usually make little or no sperm. Inheriting genetic diseases is not in the hands of anyone. Many boys with Klinefelter syndrome show few or only mild signs. The most common symptom is infertility . F1000Research. Symptoms All rights reserved. Receive personalized insights on your symptoms and treatment effectiveness with our interactive Health Chats. Kleinfelter syndrome facts author: John P. Cunha, DO, FACOEP. Eunice Kennedy Shriver National Institute of Child Health and Human Development. The syndrome can affect different stages of physical, language, and social development. The effects of Klinefelter syndrome vary, and not everyone has the same signs and symptoms. About one of every 500 males has an extra X chromosome, but many don't have any symptoms. https://www.genome.gov/Genetic-Disorders/Klinefelter-Syndrome. It is by sheer bad luck that one has to lead a life with a permanent physical disability. About one of every 500 males has an extra X chromosome, but many don't have any symptoms. Klinefelter syndrome (KS) is a condition that occurs in men who have an extra X chromosome. This can lead to a taller, less muscular body, less facial and body hair, and broader hips than other boys. Klinefelter syndrome, also known as the XXY condition, is a term used to describe males who have an extra X chromosome in most of their cells. Mayo Clinic is a not-for-profit organization. Klinefelter syndrome (47,XXY). As adults, XXY males may have a harder time doing work that involves reading and writing, but most hold jobs and have successful careers. This content does not have an Arabic version. Make a donation. The XXY chromosome pattern cannot be changed. Signs and symptoms of Klinefelter syndrome vary widely among males with the disorder. Klinefelter syndrome symptoms. 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. After about age four, XXY males tend to be taller and may have less muscle control and coordination than other boys their age. Poly-KS males might also show slight differences in other physical features. As teens, XXY males may have larger breasts, weaker bones, and a lower energy level than other boys. The XXY condition that causes Klinefelter syndrome … Klinefelter syndrome. Scientists believe the XXY condition is one of the most common chromosome abnormalities in humans. Klinefelter syndrome is a genetic condition affecting males, and it often isn't diagnosed until adulthood. National Human Genome Research Institute. Klinefelter syndrome occurs as a result of a random error that causes a male to be born with an extra sex chromosome. Deng C, et al. AskMayoExpert. Klinefelter syndrome is named after Dr. Henry Klinefelter, who first described a group of symptoms found in some men with the extra X chromosome. Kleinfelter syndrome facts author: John P. Cunha, DO, FACOEP. For others, the condition has a noticeable effect on growth or appearance. As babies, XXY males tend to be quiet and undemanding. Recent advances in managing and understanding Klinefelter syndrome. Testosterone replacement therapy reduces the risk of certain health problems, especially when therapy is started at the beginning of puberty. Klinefelter syndrome. One of the most important factors for all types of treatment is starting it as early in life as possible. In: Ferri's Clinical Advisor 2020. The primary features are infertility and small poorly functioning testicles. https://rarediseases.info.nih.gov/diseases/8705/disease. Klinefelter syndrome is a chromosomal condition in boys and men that can affect physical and intellectual development. Because not every male with an XXY pattern has all the symptoms of Klinefelter syndrome, it is common to use the term XXY male to describe these men, or XXY condition to describe the symptoms. Physical symptoms of Klinefelter syndrome include: Being born with a smaller penis, and/or undescended testicle(s). Ferri FF. "Mayo," "Mayo Clinic," "MayoClinic.org," "Mayo Clinic Healthy Living," and the triple-shield Mayo Clinic logo are trademarks of Mayo Foundation for Medical Education and Research. The risk of Klinefelter syndrome isn't increased by anything a parent does or doesn't do. The XXY chromosome pattern can not be changed. Young boys with Klinefelter syndrome might have: Klinefelter syndrome affects around 1 in every 660 males. Rank It. https://www.mayocliniclabs.com/test-catalog/Clinical+and+Interpretive/63439. Genetics Home Reference. Accessed Aug. 9, 2019. Klinefelter syndrome is a genetic condition that results when a boy is born with an extra copy of the X chromosome. Accessed Aug. 9, 2019. Scientific Reports. Klinefelter syndrome (KS). It is also known as the XXY syndrome. A single copy of these materials may be reprinted for noncommercial personal use only. Klinefelter syndrome (47, XXY) is a condition that occurs in men who have an extra X chromosome, resulting in an XXY sex chromosome karyotype. Drugs A-Z. https://www.merckmanuals.com/professional/pediatrics/chromosome-and-gene-anomalies/klinefelter-syndrome-47,xxy?query=Klinefelter%20Syndrome. Current Opinion in Endocrinology, Diabetes and Obesity. For specific syndromes, see under the name, such as adrenogenital syndrome or reye's syndrome. Klinefelter syndrome (KS) is a condition that occurs in males when they have an extra X chromosome.Some males with KS have no obvious signs or symptoms while others may have varying degrees of cognitive, social, behavioral, and learning difficulties. It affects between 1 in 500 and 1 in 1,000 newborn males. Cell-free DNA prenatal screen, blood. Klinefelter Syndrome Diagnosis. Some people are affected only very mildly, while for others it has more of an impact on their lives. Klinefelter Syndrome (47, XXY) is a chromosomal variation in males in which one extra X chromosome is present, resulting in a 47,XXY karyotype. The syndrome may also cause reduced muscle mass, reduced body and facial hair, and enlarged breast tissue. Accessed Aug. 9, 2019. Klinefelter syndrome is a fairly common genetic condition found in males only. Males with poly-X Klinefelter syndrome have more than one extra X chromosome, so their symptoms might be more pronounced than in males with KS. It is three … Bearelly P, et al. To diagnose Klinefelter syndrome, your doctor will start with a physical exam and questions about your symptoms … Clinical application of noninvasive prenatal screening for sex chromosome aneuploidies in 50,301 pregnancies: Initial experience in a Chinese hospital. But, there are a variety of ways to treat the symptoms of the XXY condition. Klinefelter syndrome, also known as the XXY condition, is a term used to describe males who have an extra X chromosome in most of their cells. It is estimated that 3,000 affected boys are born each year in the US. One such unfortunate condition is the Klinefelter syndrome. Klinefelter syndrome does not usually cause any obvious symptoms early in childhood, and even the later symptoms may be difficult to spot. Advertising revenue supports our not-for-profit mission. Klinefelter syndrome (KS), also known as 47,XXY is the set of symptoms that result from two or more X chromosomes in males. Sept. 10, 2019. ; About one of every 500 males has an extra X chromosome, but many don't have any symptoms. Most men with Klinefelter syndrome produce little or no sperm, but assisted reproductive procedures may make it possible for some men with Klinefelter syndrome to father children. Having abnormal body proportions. 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