Rose suckers

Do rose suckers always emanate from the root stock? I ask this because my 'Gepff Hamilton' rose has several new shoots which are a completely different colour, basically quite red, appearing from quite high up the bush. For example, some at least a foot from the root stock, and some smaller ones higher up still. I have always pulled the red shoots off as soon as I spot them, but haven't been to examine the plant for several days because of severely inclement weather, and now see many of these new shoots. Are they just this, ie new shoots of the named rose, or are they unwanted suckers? If the latter, I need to do something about them very soon! If not, why are they such a different colour?

Thanks for any insights into this.