Another name for klinefelter syndrome, variants or close medical condition association. Klinefelter syndrome ks is a sex chromosomal anomaly, which in most cases is characterized by 47 chromosomes instead of the usual 46. Klinefelter syndrome may adversely affect testicular growth, resulting in smaller than normal testicles, which can lead to lower production of testosterone. Klinefelter syndrome sometimes called klinefelter s, ks or xxy is where boys and men are born with an extra x chromosome. Klinefelter syndrome, variants symptoms, diagnosis. When in 1942 harry klinefelter and his colleagues described the condition carrying his name 1, its aetiology was unknown. The primary features are sterility and small testicles. About 20% are variants which include 48, xxyy, 48,xxxy, 49,xxxxy syndromes and. May 03, 2020 and klinefelter s syndrome, which is the symptoms of low testosterone in xxy and variant males, called seminiferous tubule dysgenesis, has nothing at all to do with anything but hypogonadism. Klinefelter syndrome ks, also known as 47, xxy is the set of symptoms that result from two or more x chromosomes in males. Klinefelter syndrome for parents nemours kidshealth. Dec 23, 2015 rarely, an individual may possess both an additional x and an additional y chromosome 48, xxyy.
The effects of additional x chromosomes are due to hormonal changes, decreased androgen production and increased estrogen levels 4. Apr 14, 20 professor rob mclachlan discusses klinefelter syndrome, and how it can present differently in each individual but a common feature is that all men with klinefelter syndrome will have small testes. It is the most common sex chromosome disorder, affecting 1 in 660 men. Five individuals with a variant of klinefelter s xxyy syndrome are presented. A genetic condition where males have at least one extra x chromosome or extra copies of both the x and y chromosomes in each cell. The karyotype of a person with klinefelter syndrome is usually 47,xxy, meaning that an individual has 47 autosomes, two x chromosomes, and a y chromosome. Variants of klinefelter syndrome are as followsref32 ref33. Most commonly, affected individuals are taller than average are unable to father biological children infertile. The most common variant is 47, xxy which accounts for 90% of klinefelter syndrome cases 4 6. Patients typically have intellectual challenges iq range 6080, delayed speech, learning disabilities. Sometimes, symptoms are more prominent and may include weaker muscles, greater height, poor coordination, less.
Nondisjunction of sex chromosomes during maternal meiosis 53% or paternal meiosis 47% results in 47, xxy genotype classically, although variants such as xxyy, xxxy, and xxxxy, and mosaic patterns, such as xxxxy, also exist. Klinefelter s syndrome is a sex chromosomal aneuploidy caused by an addition of x chromosome in males 47, xxy. Sometimes, symptoms are more prominent and may include weaker muscles, greater height, poor. Syndrome definition in medicine and psychology, a syndrome is the association of several clinically recognizable features, signs observed by someone other than the patient, symptoms reported by the patient, phenomena or characteristics that often occur together, so that the presence of one or more. Review article klinefelter syndrome the commonest form of hypogonadism, but often overlooked or untreated eberhard nieschlag summary background. Seminoma of the testis in a patient with 48, xxyy variant of klinefelter s syndrome. Pdf clinical and behavioural profile of a rare variant. These patients, together with five xxyy subjects recorded in the literature, show the clinical features of klinefelter s syndrome. Similar physical phenotype to 47,xxy, but males are taller and have disproportionately longer lower extremities. Mar 23, 2020 in 1942, klinefelter et al published a report on 9 men who had enlarged breasts, sparse facial and body hair, small testes, and an inability to produce sperm. Other frequent variants include 48, xxxy, 49, xxxxy, and 48, xxyy 5 6.
Therefore, you should understand that klinefelter syndrome is often considered a synonym or a condition closely related to the following. Handbook of genetic counselingklinefelter syndrome. Browse az genetic and rare diseases information center. This means that klinefelter syndrome, variants, or a subtype of klinefelter syndrome, variants, affects less than 200,000 people in the us population. Xy47, xxy mosiac, chromosome 48 xxxy, chromosome 48 xxyy, chromosome xxy, hypergonadotropic hypogonadism, primary hypogonadism, seminiferous tubule dysgenesis, xxy syndrome. Klinefelter syndrome with xyxxy mosaic klinefelters. Klinefelter syndrome a medical dictionary, bibliography. May 07, 2012 48, xxyy syndrome is a chromosomal condition, characterized by the presence of an extra x and y chromosome in males, that causes medical and behavioral problems. Klinefelter syndrome mesh descriptor data 2020 mesh. The term klinefelter syndrome ks describes a group of chromosomal disorder in which there is at least one extra x chromosome to a normal male karyotype, 46,xy. This is the most rare of the klinefelter s syndrome variants and has been reported in over one hundred cases with the frequency being approximately 1 in 85,000 newborn males duenas et al. 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. There have been reports of an even more extreme variant of klinefelters syndrome mosaic in newborn males duenas et al. Clinically, it is not clearly distinct from the more com mon xxy type of the klinefelter individual.
Variants of this syndrome with x and y polygamy are of rare occurrence. Instead of having the usual xy chromosome pattern that most males have, these men have an xxy pattern. Reviewarticle 48, xxyy, 48,xxxyand 49,xxxxy syndromes. In recent years, many males have been diagnosed with klinefelter syndrome before birth, through amniocentesis or chorionic villus sampling cvs. Entry version abbreviation entry terms 48, xxyy syndrome add 49,xxxxy syndrome add klinefelter syndrome add klinefelter syndrome, variants add. Apr, 2004 the book is designed for physicians, medical students preparing for board examinations, medical researchers, and patients who want to become familiar with research dedicated to klinefelter syndrome. Xxyy is still considered a variation of klinefelter syndrome by some definitions, mainly because the pathophysiology of the testicular dysfunction has not been shown to differ from 47, xxy, and the most current research does not suggest that there should be any differences in the evaluation and treatment of testosterone deficiency in 48, xxyy compared to 47, xxy. Klinefelter syndrome increases the risk of developing extragonadal germ cell tumors and breast cancer. The most common sex chromosomal aneuploidy in males is klinefelter syndrome, with the prevalence of 1. If you have any recommendations for sites that have helped you, please feel free to let me know and i will be glad to add to the resources below.
Sep 21, 2019 klinefelter syndrome is a genetic condition affecting males, and it often isnt diagnosed until adulthood. Individuals with 48, xxyy are usually considerably tall with small testes that do not function normally leading to infertility. Its seeming rarity may be ascribed to the subtleties of clinical manifestation in a prepubertal boy rather than dieulty in establishing the diagnosis once suspected. Most often, boys and men with klinefelter syndrome. 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. Taking into consideration the findings in xyy and xxxyy individuals, it appears that the addition of a y chromosome to xy, xxy and xxxy complexes has a variable and as yet not clearly delineated harmful effect. The primary features are infertility and small poorly functioning testicles. Other sex chromosomal aneuploidies have also been described, although they are much less frequent, with 48, xxyy. Klinefelter syndrome and its variants are the most common forms of sex chromosome aneuploidy, with a reported incidence of 1 in 500 to 1 in live births. Klinefelter syndrome, disorder of the human sex chromosomes that occurs in males, one of the most frequent chromosomal disorders in males.
Xxyy syndrome is a sex chromosome anomaly in which males have an extra x and y chromosome. Section of neurodevelopmental behavioral pediatrics, department of pediatrics, university of colorado school of medicine, aurora, co, usa. There have been reports of an even more extreme variant of klinefelter s syndrome mosaic in newborn males duenas et al. First, you will not waste time searching the internet while missing a lot of relevant information. Xxyy syndrome occurs in approximately 118,000 male births. Similar physical phenotype to 47, xxy, but males are taller and have disproportionately longer lower extremities. Often, symptoms may be subtle and many people do not realize they are affected. Sometimes, symptoms are more prominent and may include. Klinefelter syndrome is a sex chromosome disorder in boys and men that results from the presence of an extra x chromosome in cells.
Klinefelter syndrome is a fairly common genetic condition found in males only. Many boys with klinefelter syndrome also known as xxy syndrome have no signs or symptoms, and some dont even know they have it until later in life. Feb 08, 1974 the xxyy variant of klinefelter s syndrome author s transl. Autism spectrum disorder in males with sex chromosome. The primary features are infertility, small testicles and hypogonadism. The official parents sourcebook on klinefelter syndrome. Klinefelter syndrome and other sex chromosomal aneuploidies. Taking into consideration the findings in xyy and xxxyy individuals, it appears that the addition of a y chromosome to xy, xxy and xxxy complexes has a. A guide for families and individuals affected by x and y chromosome variations cover msw, virginia isaacs on. Oct 24, 2006 the term klinefelter syndrome ks describes a group of chromosomal disorder in which there is at least one extra x chromosome to a normal male karyotype, 46,xy. Learn more about the causes, symptoms, and treatment of klinefelter syndrome. Its seeming rarity may be ascribed to the subtleties of clinical manifestation in a prepubertal boy rather than difficulty in establishing the diagnosis once suspected. A fifthdigit clinodactyly and nail biting, b prominent elbows with hyperextensibility and c lower extremities with low muscle bulk in the calves, flat feet and mild pronation at the ankles.
Rare case of klinefelters syndrome with 48xxyy vasudev magaji md, debra feden crnp and gretchen perilli, md references. The appearance of at least one y chromosome with a properly. Klinefelter syndrome ks is a common genetic condition, affecting one in 450 men. Feb 14, 2018 klinefelter syndrome ks is a condition that occurs in males when they have an extra x chromosome. It results from an unequal sharing of sex chromosomes soon after fertilization. Human cells usually contain two sex chromosomes, one from the mother and one from the father. Other sex chromosomal aneuploidies have also been described, although they are much less frequent, with 48, xxyy and 48,xxxy. The xxy condition that causes klinefelter syndrome cant be changed, but medical treatment and working with. Three males with an xxyy sex chromosome complex are described. Article in german hornstein op, rott hd, schwanitz g, grosse g. Usually, females have two x chromosomes xx and males have one x and one y chromosome xy.
Breast carcinoma in association with the klinefelter syndrome. This is the most rare of the klinefelters syndrome variants and has been reported in over one hundred cases with the frequency being approximately 1 in 85,000 newborn males duenas et al. The most common variant of klinefelter syndrome similar physical phenotype to 47, xxy, but males are taller and have disproportionately longer lower extremities iq is typically reduced and ranges from 60 to 80. Xxy aneuploidy is the most common disorder of sex chromosomes in humans, with prevalence of one in 500 males. It affects between 1 in 500 and 1 in 1,000 newborn males.
They include variations in body hair, lack of acne at adolescence, multiple cutaneous angiomas, acrocyanosis, and. Klinefelter syndrome xxy, xyy, xxx, xxyy, xxxy, xxxxy and associated variants. Xxy syndrome, 47, xxy males, epidemiology of klinefelter s syndrome 1. Many with known klinefelter s syndrome are not diagnosed until they are adults. There are 2 types of chromosome, called the sex chromosomes, that determine the genetic sex of a baby. Enter your mobile number or email address below and well send you a link to download the free kindle app. April 9, 2011 sex chromosome tetrasomy and pentasomy conditions occur in 1.
The condition is not inherited but is a result of problems during cell division. Living with klinefelter syndrome 47,xxy trisomy x 47, xxx and 47, xyy. Ever since, diagnosing klinefelter s syndrome has required the demonstration of the 47, xxy karyotype or one of its rare variants. What are the genetic variants of klinefelter syndrome. Chromosomes are packages of genes found in every cell in the body. Variants of the disease with three, four, or more extra. The characteristics of the syndrome are discussed, including those signs of interest to dermatology. Klinefelter syndrome is a chromosomal condition in boys and men that can affect physical and intellectual development. We aim to increase awareness and inform the health and education sectors and broader community. 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. Living with klinefelter syndrome, trisomy x, and 47, xyy. Variants of 48xxxy and 48xxyy klinefelter syndrome.
Klinefelter s syndrome often goes undiagnosed in affected males. In 1959 jacobs and strong 2 recognized the chromosomal basis of the disorder, until then solely defined through a set of clinical criteria. Although this site implies xyy is a variant of klinefelter s syndrome, it is not, as xyys do not have atrophied testes, therefore do not have seminiferous tubule dysgenesis, which you can read. About 47,xxy the association for x and y chromosome variations. Klinefelter syndrome, variants is listed as a rare disease by the office of rare diseases ord of the national institutes of health nih. A guide for families and individuals affected by extra x and y chromosome variations thanks to the generosity of the book s author, virginia isaacs cover, msw, axys is pleased to make this book available to the x and y variation community, in its entirety, at no cost. An xxyy variant of the klinefelter syndrome in a prepubertal boy is described. People typically have 46 chromosomes in each cell, two of which are the sex chromosomes. Some males with ks have no obvious signs or symptoms while others may have varying degrees of cognitive, social, behavioral, and learning difficulties. While often compared with 47, xxy klinefelter syndrome. The xxyy variant of klinefelters syndrome authors transl. Acta androgen aneuploidy associated bandmann e breit barr barr bodies basal biopsy bone formation boys with klinefelter s breast cancer chromatinpositive chromosome anomaly clin endocrinol metab clinical controls cytogenetic decreased dermatoglyphic diagnosis drome effect estrogen eunuchoid excretion f x sw felter s syndrome female ferguson.
Klinefelter syndrome ks with the karyotype 47,xxy is one of the commonest types of congenital chromosomal disorder in males, with an incidence of 0. The 48, xxyy syndrome is generally considered the most common variant of the klinefelter syndrome 47,xxy. Patients with 48, xxyy tend to be taller and more aggressive than those with 47,xxy klinefelter syndrome. Xxyy syndrome is the name attached to the cluster of symptoms that arise as a result of the 48, xxyy chromosome pattern. Xxyy is sometimes considered a variant of another syndrome called klinefelter syndrome, or 47, xxy. Living with xxy became a nonprofit 501c3 charitable organization on november 6th, 2019. Klinefelter syndrome genetic and rare diseases information. Two of the 46 chromosomes, known as x and y, are called sex chromosomes because they help determine whether a person will develop male or female sex characteristics. Originally described as a variant of klinefelter syndrome xxy because of shared features of tall stature and hypogonadism,22 it is now recognized that xxyy is associated with more significant cognitive deficits and behavioral disorders, as well as a higher rate of. Discussion the xxyy variant is a relatively rare form of the klinefelter syndrome.
An xxyy variant of the klinefelter syndrome in a prepubertal. The syndrome was originally considered a variation of klinefelter syndrome, and xxyy is still considered a variation of klinefelter syndrome by some definitions because the pathophysiology of the testicular dysfunction has not been shown to differ from 47, xxy, and the most current research does not suggest that there should be any differences in the evaluation and treatment of testosterone deficiency in 48, xxyy compared to 47, xxy. Females have two x chromosomes 46,xx, and males have one x and one y chromosome 46,xy. May 23, 2017 klinefelter syndrome is one of the most common chromosome conditions in newborns.
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