Sp gene question

[MonoOmoi]

I was thinking the other day about one of my first liters, back when I was entirely ignorant of genetics. It was actually a pregnant gerbil I took from a pet store. She was agouti, and she had three spotted pups. I was told that the gerbils in the tank at the store were the entire liter, and thus she was pregnant by one of her brothers. Problem with this is, none were spotted. There was a REW, however. So, do REW show when they carry the Sp gene? I'm guessing he was the father if there's no way to tell. But, is there any way that two non-spotted gerbils can have spotted pups? I don't think so... but I guess the people at the pet store could have been wrong, and maybe there was another male in the tank at some point. Anyway... just curious... thanks!

[Padfoot]

I don't think that non-spotted gerbil could have... I'm not sure though... I don't know if a gerbil can actually carry the spotting gene and it doesn't show... REW could carry the spotting gene and it wouldn't show... (cause it's all white...)

[Jakamoko]

Gerbils can carry spotting modifiers, without having the usual spots ( nose, head, nape of neck, tail etc)
This can be seen in aa Gerbils (including nutmeg, Lilac, Burmese etc). For example, blacks can have white feet and a bib without actually being spotted.

If you were to breed with these types of black Gerbil then they will be carrying spotting modifiers and can often be good in the hunt for mottled or well spotted Gerbils.

I don't think you could get a Pied etc Gerbil from this though... My knowledge of breeding spotteds is not all that good.
I don't know whether a breeder would use a bibbed black with a pied/mottled gerbil to extend the spots... I would think this would be the case though, as plenty of people use these bibbed Gerbils and don't end up with spotted/pied Gerbils.