Compositional mapping of the human dystrophin-encoding gene.
The genomes of warm-blooded vertebrates are mosaics of long DNA segments (> 300 kb, on the average), the isochores, homogeneous in GC levels, which belong to a small number of compositional families. In the present work, the human dystrophin-encoding gene, spanning more than 2.3 Mb in Giemsa band Xp21 (on the short arm of the X chromosome), was analyzed in its isochore organization by hybridizing cDNA probes, corresponding to eight contiguous segments of the coding sequence, on compositional fractions from human DNA. Five DNA regions of uniform (+/- 0.5%) GC content, separated by compositional discontinuities of about 2% GC, were found, so providing the first high-resolution compositional map obtained for a human genome locus and the first direct estimate of isochore size (360 kb to more than 770 kb, in the locus under consideration). One of the isochores contains 71% and another one 21% of deletion breakpoints found in patients suffering from Duchenne's and Becker's muscular dystrophies.
Bettecken
T
T
Institut für Humangenetik, Universität Würzburg, Biozentrum, Germany.
Aissani
B
B
Müller
C R
CR
Bernardi
G
G
D003198:Computer Simulation; D004247:DNA; D015342:DNA Probes; D016189:Dystrophin / Q000235:genetics*; D017353:Gene Deletion; D006801:Humans; D009136:Muscular Dystrophies / Q000235:genetics; D014960:X Chromosome
D015342:DNA Probes; D016189:Dystrophin; D004247:DNA