G-banding involves staining protease-treated chromosomes with Giemsa dye and is thought to result from interactions of both DNA and protein with the thiazine and eosin components of the stain. The most common Rbandingmethodinvolvesheatdenaturingchromosomesin hotacidicsalinefollowedbyGiemsastaining.Thismethod is thought to preferentially denature AT-rich DNA and to stain the under-denatured GC-rich regions. T-banding identifies a subset of R-bands – the most intensely staining ones – by employing either a more severe heat treatment thanR-banding.ItisthoughttoidentifytheGC-richestRbands, of which approximately half occur at telomeres in the human genome, hence the name.