Half-breed Umbridge

[severusbook4]

No: HPFGUIDX 81118

I know this has been discussed some what but never really hit on 
what I want to ask.  Umbridge is described as short, wide, froggish 
with sharp pointed teeth, she is not much taller standing as when 
she is sitting.  Also as BBoy pointed out, she has a hatred for half-
breeds that rivels LV's hatred of mugbloods.  Could she be half 
goblin? I can't seem to find a real clear desciption of a goblin, 
but then all of my books are out on loan except OotP.  In SS (the 
movie) the goblins fit the short, with sharp teeth, and froggish 
mouth description, but can't find that in the books since I don't 
have them at this point.  A friend of mine and I are discussing this 
possibility, but have come to a screeching halt for lack of canon.  
Any help would be, well, helpful.

Sevvie, this woman makes me look positively lovable, Snape