This is Serafina, she is what we believe to be a Winter White mix. We adopted her in September, at first her coloring/markings caught my attention. However a week later that color had changed and thereafter is seems almost every week she has either different marking or is a slightly different color. We notice she has what I refer to as the 'roman nose' of a Winter White but she has never changed to an all white color, leading me to think she is a mix or as I notice on here you refer to as a hybrid. I know many captive winter white do not change color though. I am attaching a photo, please let me know what you think. She is very pretty either way and sooo friendly. She loves coming out of her cage and from the start has been very easy to handle.
She is lovely. Not all pure WW's change completely, if you see the thread about Olivia I have mentioned on there.
In fact she is the image of my sons WW Gizmo. But other than that I can't tell you either way.
I would say she could possibly be a pure Winter White, she doesn't show any obvious signs of Campbells genetics. Did you get her from a pet shop, or a breeder/rescue? Pet shop Russians are very likely to be hybrids.
Regardless, she is beautiful and I love her name! She looks like she'd be very friendly
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Olive Hamstery: breeder of quality Campbells dwarf hamsters in London.
Serafina was in a shelter here in in US, she had come with with a few others (the others being male and had been adopted). At first I just thought her markings were interesting, but later when those markings kept changing I thought she may be a WW.
She's had a slight winter moult by the looks of things, but that doesn't rule in or rule out a hamster being a hybrid.
It is generally believed that there are no pure WW in the US pet market (though a few breeders have imported them from abroad, but these are unlikely to have ended up in a rescue). Her head shape (that's not a roman nose), eye and ear position are wrong for a WW, but being a hybrid means very little in terms of whether she will be a good pet or not, so there's no reason to worry
Meet Serafina
But other than that I can't tell you either way. 
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