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The fragile site (17)(p12): induction by AT-specific DNA-ligands and population cytogenetics


The rare fragile site at 17p12 can be induced in lymphocyte cultures with the AT-specific DNA-ligands distamycin A, DAPI, Hoechst 33258 and berenil. The optimum culture conditions for the experimental induction of fra(17)(p12) were studied. There are indications that fra(17)(p12) is a latereplicating chromosome region in which AT-rich DNA is located. The fragile site also occurs spontaneously in cell cultures of most fra(17)(p12) carriers. A population screening of 250 unselected individuals showed that the frequency of carriers heterozygous for fra(17)(p12) is 2%. The results are compatible with a population being in Hardy-Weinberg equilibrium with respect to fra(17)(p12) and its non-fragile allelomorph. Neither the heterozygous nor the homozygous condition of fra(17)(p12) have any deleterious effects.

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Correspondence to M. Schmid.

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Schmid, M., Feichtinger, W., Deubelbeiss, C. et al. The fragile site (17)(p12): induction by AT-specific DNA-ligands and population cytogenetics. Hum Genet 77, 118–121 (1987).

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  • Cell Culture
  • Internal Medicine
  • Culture Condition
  • Metabolic Disease
  • DAPI