Interphase and metaphase resolution of different distances within the human dystrophin gene.
Fluorescence in situ hybridization makes possible direct visualization of single sequences not only on chromosomes, but within decondensed interphase nuclei, providing a potentially powerful approach for high-resolution (1 Mb and below) gene mapping and the analysis of nuclear organization. Interphase mapping was able to extend the ability to resolve and order sequences up to two orders of magnitude beyond localization on banded or unbanded chromosomes. Sequences within the human dystrophin gene separated by less than 100 kb to 1 Mb were visually resolved at interphase by means of standard microscopy. In contrast, distances in the 1-Mb range could not be ordered on the metaphase chromosome length. Analysis of sequences 100 kb to 1 Mb apart indicates a strong correlation between interphase distance and linear DNA distance, which could facilitate a variety of gene-mapping efforts. Results estimate chromatin condensation up to 1 Mb and indicate a comparable condensation for different cell types prepared by different techniques.
Department of Cell Biology, University of Massachusetts Medical School, Worcester 01655.
J B
JB
Lawrence
R H
RH
Singer
J A
JA
McNeil
D002871:Chromosome Banding; D002874:Chromosome Mapping; D002878:Chromosomes, Human, Pair 1; D004247:DNA / Q000235:genetics; D015342:DNA Probes; D016189:Dystrophin; D005347:Fibroblasts / Q000166:cytology; D005796:Genes; D015894:Genome, Human; D006801:Humans; D007399:Interphase; D008677:Metaphase; D009124:Muscle Proteins / Q000235:genetics*; D009693:Nucleic Acid Hybridization
D015342:DNA Probes; D016189:Dystrophin; D009124:Muscle Proteins; D004247:DNA