Induction of R-bands on human chromosomes by TfiI as the consequence of local differences in target richness
I Tagarro1, J J González-Aguilera, A M Fernández-Peralta
1Departamento de Biología, Unidad de Genética, Facultad de Ciencias, Universidad Autónoma de Madrid, Spain.
Cytogenetics and Cell Genetics
|January 1, 1992
Abstract:
We present a new restriction enzyme-banding pattern on fixed human chromosomes. R-bands are induced by TfiI, an enzyme that cuts DNA at GA(A/T)TC, that is, at HinfI sites having A or T in the central position. Results suggest that regional differences in the frequency of targets are responsible for the effect caused by this enzyme, whereas conformational differences between G- and R-bands would not affect the enzyme action.
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