R-banding methods are useful for analyzing deletions or translocations that involve the telomeres of chromosomes.
Background Reverse banding using heat and Giemsa (RHG) was first described by Dutrillaux and Lejeune. This technique involves the incubation of slides in hot phospate bufer with subsequent Giemsa staining. The resulting chromosome pattern shows darkly stained R bands and pale G bands. R bands are GC-rich and the AT-rich regions are selectively, or more readily, denatured by heat, but the GC-rich regions remain intact. This is consistent with the fact that GC-specific fluorochromes also produce a reverse chromosome banding pattern. In many laboratories, RHG methods have been abandoned in favor of a fluorescent R-banding technique (Gustashaw, 1991).
Gustashaw, KM. Chromosome Stains. In The ACT Cytogenetics Laboratory Manual, Second Edition, edited by M. J. Barch. The Association of Cytogenetic Technologists, Raven Press, Ltd., New York, 1991.