The effect of Y-chromosome alpha-satellite array length on the rate of sex chromosome disomy in human sperm
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Trisomy is the leading known cause of mental retardation and pregnancy loss in humans, yet virtually nothing is known of the underlying nondisjunctional mechanisms. Since studies of other organisms suggest an association between centromere size or sequence and meiotic nondisjunction, we recently initiated studies to examine the effect of centromere size variation on human nondisjunction. In the present report, we summarize studies correlating variation in the size of the Y-chromosome centromere with sex chromosome nondisjunction. In one set of studies, we used pulsed-field gel electrophoresis to estimate Y-chromosome alpha-satellite array lengths in normal males, and correlated these values with Y-chromosome sperm disomy levels as determined by fluorescence in situ hybridization. In a second set of studies, we determined the Y-chromosome alpha-satellite array length of 47,XYY males, since the karyotypes of these individuals are a consequence of Y chromosome nondisjunction. Neither set of studies provided evidence for an effect of Y-chromosome alpha-satellite array length on Y-chromosome nondisjunction. Thus, if there is an association between Y-chromosome centromere size and nondisjunction, the effect is subtle and below the detection levels of the present study or involves extreme size variants that were not represented in the present study population.
KeywordsMental Retardation Size Variant Detection Level Present Report Pregnancy Loss
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- Hassold T, Sherman S (1993) The origin of nondisjunction in humans. In: Chandley A, Summer A (eds) Chromosomes today, vol 11. Cambridge University Press, Cambridge, UK, pp 313–322Google Scholar
- Latin Z, Fricker MD, Tyler-Smith C (1994) De novo formation of several features of a centromere following introduction of a Y alphoid YAC into mammalian cells. Hum Mol Genet 3:689–695Google Scholar
- Spriggs EL, Martin RH (1994) Aneuploidy in 165,330 human sperm: results of two- and three-colour fluorescence in situ hybridization for chromosomes 1, 12, 15, 18, X and Y. Am J Hum Genet 55 [Suppl]: A44Google Scholar
- Wyrobek AJ, Robbins WA, Weier HU, Pinkel D (1992) Detection of human sperm carrying sex-chromosomal and autosomal aneuploidies using one, two, and three-color fluorescence in situ hybridizations. Am J Hum Genet 51 [Suppl]: A23Google Scholar