To follow the transition of dsDNA (double-stranded) to ssDNA (single-stranded), intercalating dyes are employed. These dyes show differential fluorescence emission dependent on their association with double-stranded or single-stranded DNA. SYBR Green I is a first generation dye for HRM. It fluoresces when intercalated into dsDNA and not ssDNA. Because it may inhibit PCR at high concentrations, it is used at sub-saturating concentrations.  Recently, some researchers have discouraged the use of SYBR Green I for HRM, claiming that substantial protocol modifications are required. This is because it is suggested that the lack of accuracy may result from "dye jumping", where dye from a melted duplex may get reincorporated into regions of dsDNA which had not yet melted.  New saturating dyes such as LC Green and LC Green Plus, ResoLight, EvaGreen, Chromofy and SYTO 9 are available on the market and have been used successfully for HRM.  However, some groups have successfully used SYBR Green I for HRM with the Corbett Rotorgene instruments  and advocate the use of SYBR Green I for HRM applications.