Klinefelter syndrome: Expanding the phenotype and identifying new research directions. Is it useful to modify the care of Klinefelter's syndrome to improve the chances of paternity? Because symptoms of Klinefelter syndrome (KS) can sometimes be very mild, many people are never diagnosed or treated. Instead of havin… Slideshare uses cookies to improve functionality and performance, and to provide you with relevant advertising. This chromosome is large compared with the male conferring Y sex chromosome. A 33-year-old member asked: what is the difference between down syndrome and turner syndrome? Kleinfelter syndrome facts author: John P. Cunha, DO, FACOEP. They range from highly skilled to severely challenged, yet each person has a unique set of strengths. It is named after John Langdon Down who is a British physician who described the syndrome in 1866 (Living With Down Syndrome). As this eMedTV page explains, it only affects females. This possibility occurs as males with Klinefelter syndrome and Kallmann syndrome can have delayed or absent puberty and infertility concerns. 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. Where comparisons could be made, termination rates were similar in … Down syndrome, Turner syndrome, and Klinefelter syndrome constitute the most common chromosomal abnormalities encountered by primary care physicians. However, genetic testing can easily distinguish between these two conditi Down syndrome — also known as trisomy 21 — is a condition in which a person is born with extra genetic material from chromosome 21, one of the 23 human chromosomes. It can be identified at the infant stage but being a deformity of the extra X chromosome. The differences between Down syndrome and Klinefelter syndrome are as follows: Down syndrome: It is caused by the extra 21 chromosome that is present in an offspring. This page further explores this syndrome and its causes, symptoms, and treatment options. Most people with Down syndrome have a full extra copy of chromosome 21, and so they have three copies instead of the usual two. Similarities Between Gene Mutation and Chromosomal Mutation Both gene mutation and chromosomal mutation cause alterations in the genetic material of an organism. Klinefelter syndrome is a chromosomal condition in boys and men that can affect physical and intellectual development. Top answers from doctors based on your search: Disclaimer. Down syndrome, also called Trisomy 21, is a developmental disorder which is caused by an extra copy of chromosomes 21. Instead of having the usual XY chromosome pattern that most males have, these men have an XXY pattern. They are all aneuploidy conditions that result from nondisjunction during meiosis (gametogenesis- formation of gametes). Dr. Johanna Fricke answered. Often, symptoms are subtle and subjects do not realize they are affected. Between 1-400 to 1-650 males are born with Klinefelter syndrome. The primary features are infertility and small poorly functioning testicles. However, the syndromic specificity and developmental trajectories associated with EF difficulties in these groups are poorly understood. Normally, males have 46 chromosomes with one X and 1 Y chromosome. Abstract. down syndrome vs turner syndrome. 4 Two of the patients were adults, and these men had … Reaction range — … For Down's syndrome, the 47th … The correlations for stature between parents and grown-up offspring in 90 normal males and 116 normal females have been compared with similar correlations obtained in 27 adult males with Klinefelter's syndrome, 33 adult females with Turner's syndrome and in 75 adult patients with Down's syndrome. Both syndrome's indicate the presence of a 47th chromosome (or extra part of a chromosome). Ask doctors free. Klinefelter syndrome and Turner syndrome are sex chromosomal abnormalities. Down syndrome (47, +21) is the presence of an extra #21 chromosome; Klinefelter syndrome is the presence of an extra X chromosome (47, XXY); Turner syndrome is the absence of a second sex chromosome (45, XO). There was close similarity between the findings in the patients with sex chromosomal disorders and in … They were highest following a prenatal diagnosis of Down syndrome (92 per cent; CI: 91 per cent to 93 per cent) and lowest following diagnosis of Klinefelter syndrome (58 per cent; CI: 50 per cent to 66 per cent). Klinefelter syndrome (KS), also known as 47,XXY is the set of symptoms that result from two or more X chromosomes in males. When a diagnosis is made, treatment is based on the signs and symptoms present in each person, especially the problems related to hypogonadism, gynecomastia, and psychosocial problems. Turner's syndrome and Klinefelter's syndrome involve abnormalities in the X sex chromosome. Down syndrome, Turner syndrome, and Klinefelter syndrome: Primary care throughout the life span October 2004 Primary Care Clinics in Office Practice 31(3):627-48, x-xi The Human Genome Project – humans have 30,000 genes. An individual with Swyer syndrome (46, XY) differs from an individual with Klinefelter syndrome (47, XXY) because an individual with Klinefelter syndrome has a functional SRY gene on his Y chromosome, whereas an individual with Swyer syndrome does not. 49 years experience Developmental and Behavioral Pediatrics. All human chromosomes usually occur in pairs, with one copy inherited from a person’s mother and one from the father. 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. Three examples of genetic disorders are Down syndrome, Turner syndrome, and Breast/Ovarian cancer. 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. Executive functions (EF) are thought to be impaired in Down syndrome (DS) and sex chromosome trisomy (Klinefelter and Trisomy X syndromes; +1X). 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. The presence of a Y chromosome is necessary for an individual to be male. Klinefelter syndrome, also known as XXY syndrome, is a condition in boys and men that’s caused by an extra X chromosome. Treatment may include: Testosterone replacement: About half of people with … In 1959, Down syndrome was shown to be associated with an extra chromosome in the G group 1; Klinefelter syndrome was associated with an extra X chromosome 2; and a case of double aneuploidy, a 48,XXY,G + male, was reported. Annales … A Overview and Research Project on the chromosomal disorder known as Klinefelter Syndrome by Ian Layden for Ms. Brown's AP Biology class. 3 In 1971, Erdtmann et al summarized 16 cases with this form of double aneuploidy. Females have two X chromosomes (46,XX), and males have one X and one Y chromosome (46,XY). Genetics in Medicine, 5(6), 460-468. It can affect physical and mental development. Turner syndrome is characterized by complete or partial absence of one of the two X chromosomes. Plotton, I., Brosse A., & Lejeune, H. (2010). People typically have 46 chromosomes in each cell, two of which are the sex chromosomes. ; About one of every 500 males has an extra X chromosome, but many don't have any symptoms. • Down Syndrome Trisomy 21 (three) • Turner Syndrome (XO) • Klinefelter Syndrome (XXY) Polygenic inheritance In most cases, many genes interact to produce a particular characteristic. Klinefelter Syndrome . If the effects of Klinefelter syndrome are compared to the effects of Down Syndrome, this disorder is a. more severe than Down syndrome, due to gene deletions in this syndrome b. more severe than Down syndrome, due to trisomy in Klinefelter syndrome c. less severe than Down syndrome, due to monosomy in Down Syndrome Most humans have 23 pairs of chromosomes, totaling 46 chromosomes. Down's syndrome is caused by trisomy of chromosome 21—one of the smallest chromosomes. Because Klinefelter syndrome falls on a spectrum, though there are many similarities, people with Klinefelter syndrome often learn, think and interact differently than others. Multimedia. Down syndrome is an autosomal chromosomal abnormality. Klinefelter syndrome is caused by the addition of an X chromosome. Klinefelter syndrome is a sex chromosome disorder in boys and men that results from the presence of an extra X chromosome in cells. In the case of Klinefelter syndrome, the male has 2 X chromosomes and 1 Y chromosome (Figure 1). Klinefelter syndrome may be confused with the genetic condition Kallmann syndrome.