Kleinfelter's Syndrome
Kleinfelter's Syndrome or XXY Syndrome is a condition in which males have an extra X sex chromosomes. People affected by Kleinfelter's have atleast two X chromosomes and atleast one Y chromosomes. Kleinfelter's is the most common sex chromosome disorder. Kleinfelter's exsists in 1 out of every 1000 males, but 1 out of every 500 have the extra X chromosome but do not have the disease. The principle effects of Kleinfelter's are developements of small testicles and reduced fertility. A variety of other physical and behavioral differences and problems are common, through severity varies and many boys men with the condition have few detectable symptoms. Kleinfelter's was first described in 1942 by Dr. Harry Kleinsfelter, an endocrinologist at Massachusetts General Hospital in Boston, Massachusetts. Affected males may to some degree have a language learning impairment. To diagnose Kleinfelter's doctors use karyotypes. In this procedure, a small blood sample is drawn. White blood cells are then separated from the sample, then mixed with tissue culture medium, incubated, and checked for chromosomal abnormalities, such as an extra X chromosome.The extra X chromosome is retained because of a nondisjunction event during meiosis (sex cell division). The XXY chromosome arrangement is one of the most common genetic variations from the XY karyotype, occurring in about 1 in 500 live male births. In mammals with more than one X chromosome, the genes on all but one X chromosome are not expressed; this is known as X inactivation. This happens in XXY males as well as normal XX females. However, in XXY males, a few genes located in the pseudoautosomal regions of their X chromosomes, have corresponding genes on their Y chromosome and are capable of being expressed.These triploid genes in XXY males may be responsible for symptoms associated with Klinefelter's syndrome. The genetic variation is irreversible.Testosterone treatment is an option for some individuals who desire a more masculine appearance and identity. Often individuals that have noticeable breast tissue, hypogonadism, experience depression, and/or social anxiety because they are outside of social norms. This is academically referred to as psychosocialmorbidity. At least one study indicates that planned and timed support should be provided for young men with Klinefelter syndrome toameliorate current poor psychosocial outcomes. http://www.slh.wisc.edu/cytogenetics/cases/gifs/com_karyotypes/CoMNov97karyo.gif http://intramural.nimh.nih.gov/chp/images/xygraphic4.jpg
Kleinfelter's Syndrome
Kleinfelter's Syndrome or XXY Syndrome is a condition in which males have an extra X sex chromosomes. People affected by Kleinfelter's have atleast two X chromosomes and atleast one Y chromosomes. Kleinfelter's is the most common sex chromosome disorder. Kleinfelter's exsists in 1 out of every 1000 males, but 1 out of every 500 have the extra X chromosome but do not have the disease. The principle effects of Kleinfelter's are developements of small testicles and reduced fertility. A variety of other physical and behavioral differences and problems are common, through severity varies and many boys men with the condition have few detectable symptoms. Kleinfelter's was first described in 1942 by Dr. Harry Kleinsfelter, an endocrinologist at Massachusetts General Hospital in Boston, Massachusetts. Affected males may to some degree have a language learning impairment. To diagnose Kleinfelter's doctors use karyotypes. In this procedure, a small blood sample is drawn. White blood cells are then separated from the sample, then mixed with tissue culture medium, incubated, and checked for chromosomal abnormalities, such as an extra X chromosome.The extra X chromosome is retained because of a nondisjunction event during meiosis (sex cell division). The XXY chromosome arrangement is one of the most common genetic variations from the XY karyotype, occurring in about 1 in 500 live male births. In mammals with more than one X chromosome, the genes on all but one X chromosome are not expressed; this is known as X inactivation. This happens in XXY males as well as normal XX females. However, in XXY males, a few genes located in the pseudoautosomal regions of their X chromosomes, have corresponding genes on their Y chromosome and are capable of being expressed.These triploid genes in XXY males may be responsible for symptoms associated with Klinefelter's syndrome. The genetic variation is irreversible.Testosterone treatment is an option for some individuals who desire a more masculine appearance and identity. Often individuals that have noticeable breast tissue, hypogonadism, experience depression, and/or social anxiety because they are outside of social norms. This is academically referred to as psychosocial morbidity. At least one study indicates that planned and timed support should be provided for young men with Klinefelter syndrome toameliorate current poor psychosocial outcomes.
http://www.slh.wisc.edu/cytogenetics/cases/gifs/com_karyotypes/CoMNov97karyo.gif
http://intramural.nimh.nih.gov/chp/images/xygraphic4.jpg
All information was taken by the following site:http://en.wikipedia.org/wiki/Klinefelter's_syndrome