IN SUPPORT OF THE TELOMERE CONCEPT

Paul A. Roberts ¹

¹ Department of Zoology, Oregon State University, Corvallis, Oregon 97331

The frequency of recovered X-ray-induced (4000R) rearrangements that, in all probability, mimic terminal deletions of the X chromosome was only one of, roughly, 10⁵ X chromosomes screened for tip deficiencies. Although the single exception looks terminally deleted, it is probably capped by a very short or nonpolytene telomeric segment. It is apparent from these data that the probability of "healing" or stabilization of a terminally deleted X in the zygotic nucleus or developing embryo of Drosophila melanogaster is vanishingly small. The telomeric caps in two obviously interstitial deficiencies that were recovered represent, roughly, 1/500 of the length of a mitotic chromosome. These findings give some indication of the extreme difficulty of detecting short telomeric segments capping either deleted polytene chromosomes or deleted metaphase chromosomes of, for example, humans.

This article has been cited by other articles:

				A. Kasravi, M. F. Walter, S. Brand, J. M. Mason, and H. Biessmann Molecular Cloning and Tissue-Specific Expression of the mutator2 Gene (mu2) in Drosophila melanogaster Genetics, July 1, 1999; 152(3): 1025 - 1035. [Abstract] [Full Text]