I have an XY cell line I am measuring telomere length on, and I am using an XX cell line (with abnormally long telomeres) as an internal control. I would like to identify each separately, but that would require specific probes and a setup with flowFISH. I can do with just the ratio of XY/XX cells, and in this way calculate the same ratio in telomere length, giving me a relative length for each insult i put my XY cells through.