In 1942, Dr. Harry Klinefelter and his coworkers at the Massachusetts General Hospital in Boston published a report about nine men who had enlarged breasts, sparse facial and body hair, small testes, and an inability to produce sperm. By the late 1950s, researchers discovered that men with Klinefelter syndrome, as this group of symptoms came to be called, had an extra sex chromosome, XXY instead of the usual male arrangement, XY. Based on these studies, the XXY chromosome arrangement appears to be one of the most common genetic abnormalities known, occurring as frequently as 1 in 500 to 1 in 1,000 male births. Chromosomes and Klinefelter Syndrome
Women usually inherit two X chromosomes-one from each parent. Men tend to inherit an X chromosome from their mothers, and a Y chromosome from their fathers. Most males with the syndrome Dr. Klinefelter described, however, have an additional X chromosome-a total of two X chromosomes and one Y chromosome.
For In Vitro Diagnostic Use
The AneuVysion Assay (CEP® 18, X, Y-alpha satellite, LSI® 13 and 21) Multi-color Probe Panel is intended to use CEP 18/X/Y probe to detect alpha satellite sequences in the centromere regions of chromosomes 18, X and Y and LSI 13/21 probe to detect the 13q14 region and the 21q22.13 to 21q22.2 region. The AneuVysion kit is indicated for identifying and enumerating chromosomes 13,18, 21, X and Y via fluorescence in situ hybridization (FISH) in metaphase cells and interphase nuclei obtained from amniotic fluid in subjects with presumed high risk pregnancies. It is not intended to be used as a stand alone assay for making clinical decisions. FISH results are intended to be used as an aid in the diagnosis of numerical abnormalities of chromosomes 13, 18, 21, X and/or Y in conjunction with other information currently used in prenatal diagnosis, consistent with professional standards of practice1. This device is intended for use only with amniocyte cells; it is not intended for and has not been validated for use with other test matrices. This FISH assay will not detect the presence of structural chromosome abnormalities that can also result in birth defects. This FISH assay will be performed in cytogenetic laboratories.
1American College of Medical Genetics (ACMG). Technical and clinical assessment of fluorescence in situ hybridization: an ACMG/ASHG position statement. I. Technical considerations. Genetics in Medicine (2000) 2 6:356-61.
