Structural and numerical chromosomal aberrations may affect either the autosomes or gonosomes and are a common cause of spontaneous abortions. Intellectual impairment andor neuropsychiatric disorder are present in many cases. Are males with klinefelter syndrome ks more prone to weight gain. It is characterized by the presence of an extra x chromosome, which results in the karyotype 47, xxy. Close to 15% are mosaic cases, usually with two cell lines 47,xxy and 46,xy and rarely with further cell lines. The johns hopkins klinefelter syndrome center is the only multidisciplinary program of its kind in the country serving adult males, says endocrinologist adrian dobs, the centers director.
Trisomy 21 is associated with a rate of incidence of 1. Introduction the sex chromosome trisomies 47, xxy klinefelters syndrome ks and 47,xyy are the most common male sex chromosome aneuploidies compatible with live birth. Boys may be taller than other boys their age, with more fat around the belly. Introduction chromosomal aberrations ca are one of the important biological consequences of human exposure to ionizing radiation and other genotoxic agents. In klinefelters syndrome there is an xxy sex chromosome constitution. Genetic counseling in a patient with xxyxxxyxy mosaic. Who laboratory manual for the examination of human. Klinefelter syndrome ks is the most common chromosomal aberration in men. Recent advances in managing and understanding klinefelter. Endocrinological issues and hormonal manipulation in. Klinefelter syndrome is one of the numerical chromosomal aberrations involving the maldistribution of the gonosomes. Klinefelter syndrome occurs when a boy is born with one or more extra x chromosomes. Recent prospective, unbiased studies have clarified many of the previous misconceptions associated with klinefelter. Il6 is associated with insulin resistance and is an.
Klinefelter syndrome is one of the most common chromosomal disorders, occurring in one to two per 1,000 live male births. Klinefelters syndrome ks and 47,xyy are the most common male sex chromosome aneuploidies compatible with live birth. The most frequent chromosomal aberration is klinefelters syndrome, which is associated with small, solid testes with hyalinized tubules, missing spermatogenesis, and infertility. However at this time, the cause of the increased body fat, especially in the abdominal stomach area, is not known. About 8090% of ks cases bear this original karyotype, whereas the remaining exhibit in decreasing frequency varying mosaicism e. The syndrome can affect different stages of physical, language, and social development.
Sometimes, symptoms are more prominent and may include weaker muscles, greater height. Enable javascript to view the expandcollapse boxes. They believed that the hypogonadism arose primarily from failure. Pdf pattern of chromosomal aberrations in patients from. Most diabetes of this syndrome shows insulin resistance. The majority of klinefelters individuals have an extra female chromosome, resulting in an xxy pattern and a total of 47 chromosomes instead of 46. Chromosomal aberrations with endocrine relevance turner. Sep 20, 20 boys and men with the chromosomal disorder klinefelter syndrome, or xxy male, have a new resource for treatment and medical management. Rheumatic diseases and klinefelters syndrome klinefelters syndrome ks is not a rare gono somal aberration occurring in males. Other patterns of chromosomal aberration such as xxy, xxyy, and some mosaic patterns may result in the same syndrome. Mental deficiency, manic depressive psychoses, and schizophrenia seem not to occur more commonly in this syndrome than in controls. Pdf klinefelter syndrome is the most common sex chromosome disorder in males. Early recognition and hormonal treatment of the disorder can substantially improve quality of life and prevent serious consequences.
Testicular tissue extraction in a young male with 47, xxy klinefelter s syndrome. The most frequent type of intersexuality, one per 500700 live male births. This extra chromosome results in extra protein production and upsets the bodys balanced systems. Klinefelter syndrome is a chromosomal condition in boys and men that can affect physical and intellectual development. Recent research has shown that males with klinefelter syndrome ks have increased body fat and reduced muscle mass. People with this condition are born with at least one extra x chromosome. Klinefelter syndrome is the most common chromosomal aberration in men 3 11. Design registerbased cohort study comparing the incidence of convictions among men with ks and with 47,xyy with age and calendarmatched samples of the general population. Ks affects 167 per 00 men,1e3 while the prevalence estimates of 47,xyy are highly variable, ranging in live born men from 26 per 004 to 375 per 00,5 although many are not diagnosed or diagnosed late. Chronic proinflammation is involved in the pathogenesis of diabetes, and cytokines play a role in insulin resistance 1,2,3. Although extensively studied, the pathophysiology, i.
Chromosomal studies have long promised to become a kind of visible chemistry 1. Pdf klinefelters syndrome and cardiovascular disease. Klinefelter syndrome ks is a common disorder that affects 1 in 500 male patients and results in testicular failure, androgen deficiency, and impaired spermatogenesis. A chromosomal disorder, anomaly, aberration, or mutation is a missing, extra, or irregular portion of chromosomal dna. According to the current study, the pattern of chromosomal aberrations in north east of iran demonstrates the importance of cytogenetic evaluation in patients who show clinical.
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. Human genetics chromosomal aberrations medical library. 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. Klinefelters syndrome was first described in 1942 as an endocrine disorder characterised. Xxy definition klinefelter syndrome is a chromosomal disorder that affects only males. The etiology was thought to be due to an endocrine disorder of unknown cause, until 1959, when jacobs et al recognized that klinefelter syndrome was a chromosomal. There are approximately 250,000 men with ks in the united states, and the prevalence of ks in male reproductive practices is 3 to 4 %.
Chromosomes are packages of genes found in every cell in the body. Interleukin il8 is a cytokine secreted by monocytes and endothelial cells 6. Parameters for diagnosis of the syndrome are constantly expanding as new anatomical and hormonal abnormalities are noted, yet klinefelter s remains underdiagnosed and underreported. Chromosomal aberrations knowledge for medical students. Induction of chromosomal aberrations by carbamate fungicide in fish clarius batrachus asian catfish ajay singh and. Aberration alters the chromosome structure but do not involve a change in chromosome number. Klinefelter s syndrome ks is the most common sex chromosomal aberration among men, with estimated prevalence of about 1 in 500 newborn males. The chromosomal aberration found in ks is due to either meiotic or.
Klinefelter s syndrome ks is the most common chromosome aneuploidy in males, characterized by at least one supernumerary x chromosome. Diagnosis of klinefelter syndrome in the donor after. For example, in a cytogenetic study on a large dutch infertile population 1792 infertile men as low as 72 cases 4% with chromosomal abnormalities were reported and klinefelter s syndrome either pure or mosaic form was found in just 12 patients 0. Klinefelter syndrome definition, symptoms, treatment. During pregnancy chromosomal abnormalities can cause the death of an embryo or fetus. The mechanics signify chiefly a rearrangement through loss, gain or reallocation of chromosomal segments. The primary features are infertility and small poorly functioning testicles. The association of two preuterine induced conditions. Despite having fertility tests and undergoing ivf, klinefelter was not diagnosed in andrew for over forty years. It can be from a typical number of chromosomes or a. Down syndrome is the result of an extra, third copy of chromosome 21 being present in a person. Having extra x chromosomes can cause a male to have some physical traits unusual for males.
Open access research criminality in men with klinefelter. The classical phenotype of ks is widely recognized, but many affected subjects present only very mild signs. Klinefelter syndrome is the most common chromosomal abnormality in humans. Chromosomal aberrations in human disease the american. Apr 29, 20 mosaic or mosaicism mosaic or mosaicism donates the presence of two or morepopulations of cells with different genotypes in oneindividual who has developed from a single fertilized egg males with klinefelter syndrome may have a mosaic47,xxy46,xy constitutional karyotype and varyingdegrees of spermatogenic failure. Novel genetic aspects of klinefelters syndrome molecular. Klinefelters syndrome definition of klinefelters syndrome.
Mosaic chromosomal patterns found in klinefelters syndrome. Sep 21, 2019 klinefelter syndrome is a genetic condition affecting males, and it often isnt diagnosed until adulthood. It was first described in 1942, with a number of additional conditions, characteristics, and abnormalities described in later publications. Some males with ks have no obvious signs or symptoms while others may have varying degrees of cognitive, social, behavioral, and learning difficulties. The syndrome was first identified and described in 1942 by harry fitch klinefelter jr. According to the current study, the pattern of chromosomal aberrations in.
Aug 24, 20 in general, the findings of this study are in accordance with most investigations which confirm the xxy aneuploidy to be the most prevalent chromosomal aberration in infertile male 25, 12, 17, 19. Klinefelter syndrome, 47, xxy ks, occurs in about 150 per 100,000 males and is the most frequent chromosomal aberration in males. It is a subject of interest because of its wide spectrum of clinical manifestations, which include certain physical features, cognitive delays, and azoospermia. His story highlights the importance of healthcare professionals being able to describe clinical features of common chromosomal disorders and identify patients with genetic conditions such as klinefelter syndrome ms3. Klinefelter syndrome ks is a condition that occurs in men who have an extra x chromosome. Harry klinefelter and his coworkers first described the combination of features that has come to be recognized as klinefelter syndrome. Jun 4, 2019 klinefelter syndrome is a genetic disorder that affects males. Feb 14, 2018 klinefelter syndrome ks is a condition that occurs in males when they have an extra x chromosome. Klinefelter syndrome definition of klinefelter syndrome by. Physician update new hope for those with klinefelter syndrome. The syndrome was first identified and described in 1942 by harry fitch klinefelter, jr.
Often, symptoms may be subtle and many people do not realize they are affected. Klinefelter syndrome, disorder of the human sex chromosomes that occurs in males, one of the most frequent chromosomal disorders in males. Clinical and therapeutic aspects of klinefelters syndrome. Klinefelter syndrome congenital defects jama internal.
The other pattern is called the mosaic xxy syndrome, or chromosomal mosaicism, and affects approximately six percent of. 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. Fill in the origin of the aneuploid zygote in the right part of the scheme b fill in the scheme of nondisjunction in paternal meiosis i that leads to the birth. Review article klinefelter syndrome the commonest form of hypogonadism, but often overlooked or untreated eberhard nieschlag summary background. Pdf klinefelter s syndrome ks is the most common sexchromosome male disorder, characterized by one or more extra x chromosomes. Patients with klinefelter syndrome have an increased risk of extratesticular germ cell tumors and possibly increased risk of breast cancer. 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. They felt that the colobomamight occasionally be part of the phenotypic expression of klinefelter syndrome. Klinefelter syndrome symptoms and causes mayo clinic. No one knows what puts a couple at risk for conceiving an xxy child. Pattern of chromosomal aberrations in patients from north. 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. Jan 28, 2019 klinefelter syndrome ks is a common male chromosomal disorder 47, xxy that has been a topic of intrigue and inquiry since the 1940s, when it was first described 1.
These alterations arise spontaneously from errors in the normal processes of the cell. Klinefelter s syndrome results from an aberration of sex chromosomes 47, xxy karyotype which can be due to a corresponding author. Kotzot division for human genetics, department for medical genetics, molecular and clinical pharmacology, innsbruck medical university, innsbruck, austria on 1 of the 2 x chromosomes or accordingly on the y chromosome, as well as xx males and true hermaphrodites. Klinefelter syndrome ks is a common male chromosomal disorder 47, xxy that has been a topic of intrigue and inquiry since the 1940s, when it was first described 1. Learn more about the causes, symptoms, and treatment of klinefelter syndrome. Chromosomeklinefelter syndromesex chromosome abnormalities. Klinefelter syndrome is a genetic condition affecting males, and it often isnt diagnosed until adulthood.
There are approximately 250,000 men with ks in the united states, and the prevalence of ks in male reproductive practices is 3 to 4%. Klinefelter syndrome is a genetic condition that results when a boy is born with an extra copy of the x chromosome. Rare combination of becker muscular dystrophy and klinefelter. It is of note, though, that chromosomal aberrations, and among them klinefelter s syndrome may predispose to haematologic malignancies. Early recognition and hormonal treatment of the disorder can substantially improve quality of life and prevent serious. In almost all patients with klinefelter syndrome, sejdromu elevation of serum fsh is seen in lab findings 6,9, testicular dysgenesis affecting the seminiferous lkinefelter principally, with chromatinpositive nuclei. In epidemiological studies, it has been shown that. An example of a chromosomal genetic disorder is down syndrome. Klinefelter syndrome ks describes the phenotype of the most common sex chromosome abnormality in humans and.
Psychiatric aspects of klinefelters syndrome american. Chromosomal disorders form a category of human genetic diseases, that are manifested by developmental and reproductive abnormalities, as well as playing an. Other types of chromosomal aberrations are considered. Klinefelters syndrome is a sex chromosomal aberration of male infertility. Klinefelter syndromea clinical update the journal of. Novel genetic aspects of klinefelters syndrome oxford academic. Anatomical and clinical aspects of klinefelters syndrome. Klinefelter s syndrome, the most common sex disorder associated with chromosomal aberrations, is characterized by a plethora of clinical features.
What are the complications of klinefelter syndrome. Klinefelter syndrome klinefelter syndrome is one of the numerical chromosomal aberrations involving the maldistribution of the. In some cases, the features of the condition are so mild that the condition is not diagnosed until puberty or adulthood, and researchers believe that up to 75. Approximately 1 in 5001,000 males are born with an extra sex chromosome. Klinefelter syndrome ks, also known as 47, xxy is the set of symptoms that result from two or more x chromosomes in males. Case report of klinefelters syndrome with severe diabetes. A biological accident occurs during a process called meiosis causing xxy. Another typical, although not consistently reported, symptom of this disorder is gyneco mastia with almost normal male secondary sex characteristics. Ks has a genetic background, with characteristics involving numerous specialties. Klinefelter syndrome sometimes called klinefelter s, ks or xxy is where boys and men are born with an extra x chromosome. The classic clinical features of patients with klinefelter syndrome start to become recognizable during adolescence.
Multiple choice questions on human genetic disorders mcq. Meiosis is experienced by all cells which will become an egg or sperm. Ks affects 167 per 00 men,1e3 while the prevalence estimates of 47,xyy are highly variable, ranging in live born men from 26. The prevalence of chromosomal abnormalities is inversely proportionally related to sperm count. Praderwilli syndrome is a complex multisystem imprinting disorder characterized by hypothalamic dysfunction, neurological implications, and psychiatric disturbances. There are 2 types of chromosome, called the sex chromosomes, that determine the genetic sex of a baby. Pdf klinefelters syndrome ks is the most common chromosomal aberration among men and is associated with multiple psychiatric. What is the pathophysiology of klinefelter syndrome. Chromosome aberration an overview sciencedirect topics.
Among the chromosomal abnormalities, sexual chromosomal abnormalities were found in some cases, and klinefelter syndrome with 2. The mosaic xxy syndrome occurs only after conception from a mistake in cell division stewart. It results from an unequal sharing of sex chromosomes soon after fertilization. While about 2% of all infertile men have a congenital chromosomal aberration, among men with azoospermia the figure reaches 15% schmid and schmidtke 1983. However, males with klinefelters syndrome have an extra x chromosome 47xxy and therefore a total of 47 chromosomes. Klinefelter syndrome genetic and rare diseases information.
Trisomy 21, also referred to as downs syndrome, is a chromosomal aberration characterized by the presence of an additional chromosome 21. By the late 1950s, researchers discovered that men with this group of. Klinefelters syndrome is a genetic disorder found in males and affects male sexual development. Pdf case of klinefelters syndrome in an 18 year old male. Klinefelter s syndrome is a chromosomal abnormality resulting in hypogonadism. Klinefelter syndrome is a chromosomal disorder that affects only males. However, within populations there can be found abnormalities involving the structure or number of chromosomes. Klinefelters syndrome is a numeric sex chromosome aberration 47,xxy caused by meiotic nondisjunction.
Turner and klinefelter syndromes are the most common chromosome abnormalities compatible with life. Klinefelter syndrome may adversely affect testicular growth, resulting in smaller than normal testicles, which can lead to lower production of testosterone. Klinefelter syndrome ks is a common male chromosomal dis order 47. Most commonly, affected individuals are taller than average are unable to father biological children infertile. Klinefelter syndrome is a chromosomal abnormality characterized in 80% of cases by a set of chromosomes 47 xxy and 20% from xxxy karyotype, xxyy or frameworks such as mosaicism 47xxy46xx, 47xxy46xy, etc despite chromosome damage, in a female genotype, the y chromosome would prevail, leading to the male phenotype. Chromosomal variants in klinefelter syndrome fulltext sexual. The syndrome in which individual somatic cell contains three sex chromosome xxx is called. In normal course of celldivision cycle, the chromosomes duplicate and segregate in an orderly manner. Patau syndrome, klinefelter syndrome, edwards syndrome, down syndrome, xxy, trisomy 21, trisomy 18, trisomy. Klinefelters syndrome is caused by an extra x chromosome and affects only males. Autosomal aberrations that are frequently observed are trisomy patau syndrome, trisomy 18 edwards syndrome, and the most common and widely recognized chromosomal aberration, trisomy 21 down syndrome.
In 1942, klinefelter et al published a report describing nine men with a constellation of features. The sequence of gene loci in the chromosome also maintains an. The numerical chromosome aberrations in klinefelters syndrome arise by. Klinefelter s syndrome ks was first described in 1942 klinefelter et al. The chromosome set of a species remains relatively stable over long periods of time.