Well, the marked ferrets are probably more likely to come from pet stock than some of the others. Pet stock ferrets, ****no matter what the markings**** could be more likely to be bred from generations of cuddlers, depending on the temperament choices of the breeder than those not bred for cuddling as a primary choice. (There was a similar temperament problem here decades ago when a number of the ferrets sold were from fur stock; those also tended to have impaired health and longevity, BTW. Sometimes when the primary "use" being bred for is not related to temperament then personalities can be -- let's say -- non-cuddly the same as for anything else not bred for that aspect of temperament. Alternatively, when the primary focus of breeding is appearance instead of health or longevity then both of those can be sorely impacted in bad ways.) Those sorts of marking, though, are way too likely to be associated with a number of health and longevity problems. Here is a post from a genetics professor which can get you started on these neural crest genetic variations, and what are those kinds of markings and what are not: http://ferrethealth.org/archive/browse.php?msg=YG3069 You can find a lot more in the archives of http://groups.yahoo.com/group/Ferret-Genetics/ -- Sukie (not a vet, and not speaking for any of the below in my private posts) Recommended health resources to help ferrets and the people who love them: Ferret Health List http://www.smartgroups.com/groups/ferrethealth FHL Archives http://ferrethealth.org/archive/ AFIP Ferret Pathology http://www.afip.org/ferrets/index.html Miamiferrets http://www.miamiferret.org/fhc/ International Ferret Congress Critical References http://www.ferretcongress.org [Posted in FML issue 5222]