Thank you for that explanation, zuzu.
Perhaps that is what happened to the Winchester Cathedral Rose that I purchased for my new place. It turned out to have totally pink blossoms, except for one bottom branch that had white blossoms.
![Thumb of 2017-09-16/HemNorth/4dd5cc](/pics/2017-09-16/HemNorth/4dd5cc-lb.jpg)
I was so disappointed to not have my white rose, that I gave it away.