Summary
Fragile X chromosome preparations were analyzed at levels of up to 850 bands per haploid set. We were able to consistently sublocalize the Xqter fragile site to band Xq27.3 using high-resolution methods. Chromosome length versus the frequency of fragile X expression was also compared. The fragile site appeared at a higher percentage in more condensed chromosome preparations. The importance of this finding is that high-resolution chromosome preparations do not optimize fragile-X detection.
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Krawczun, M.S., Jenkins, E.C. & Brown, W.T. Analysis of the fragile-X chromosome: localization and detection of the fragile site in high resolution preparations. Hum Genet 69, 209–211 (1985). https://doi.org/10.1007/BF00293026
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DOI: https://doi.org/10.1007/BF00293026