Upon getting her papers (her AQHA # is 4247149: Deep Blue Hancock, by TW Drift Han Lucky, out of WT Miss Blue Hancock), I see the back of it says "This horse has an ancestor known to carry HYPP." I'm thoroughly confused, as I'm unaware of any of the horses on her papers here carrying HYPP.
The plot thickens, though!
Her sire's dam is out of "CO BAR EIGHTY" (2183776), by "UNKOWN SIRE" (0444444). The mare was foaled in 1984, but the unknown sire was foaled in 1901. I'm guessing 0444444 is the standard AQHA answer to an unknown sire for a horse they consider legitimate for whatever reason...
Could 0444444 Unknown Sire be a sort of "mechanical flag" that popped up the "Your horse could carry HYPP" tag to be printed on the back of the paper? Does that make sense? Or does someone see a horse they actually recognize in these bloodlines somewhere to be a real carrier of HYPP? I don't see her lines up on AllBreed, but I suppose I could probably plug them in if it would be easier than someone looking through the AQHA database.
Thanks, all. Let me know if you need further clarification!