From:
sukiec@optonline.net
Date: 2004-08-26 19:52:19 UTC
Subject: RE: Panda ferrets
To: ferrethealth@smartgroups.com
Message-ID: <482065.1093549939263.JavaMail.root@thallium.smartgroups.com>
2nd part:
Okay, the picture gets even more complicated. Not only are there multiple =
types of neural crest genetic medical disorders, but some have multiple gen=
etic routes to get those markings and these are located in different loci (=
genetic locations) so a ferret can have MULTIPLE neural crest genetic varia=
tions at the same time. It can be, therefore, that some with the worst res=
ults have a multiple dose of these mutations. =
What is a neural crest genetic variant which causes such medical disorders =
and why are the signs so widely spaced: Okay. That actually is easy to ex=
plain. In early fetal stages there are only a few cells (which is why the =
fetal cells used usually for stem cell research are from fetus that are so =
early that they are only a hollow ball of cells -- the ones unused for impl=
antation which are otherwise thrown away). Now, you know from reading abou=
t stem cells that very early fetal cells have the ability to form many type=
s of tissue. As fetal development continues there wind up being cells whic=
h are more specific in terms of what they can diversify into. One such gro=
up is the Cardiac Neural Crest. This develops into heart tissue, vascular =
tissue, head pigmentation, some intestinal aspects, some skull bone formati=
on, some ear development which is shared with pigmentation for it's basis, =
etc. If the mutation is to Cardiac Neural Crest cells then there is also a=
n increased chance of heart problems with usually but not always result in =
fetal death, kit death, or still births. If the mutation involves cells th=
at arise after the Cardiac Crest cells differentiate from the Neural Crest=
cells then those ferrets do not also have the circulatory risks.
Remember that these are very early in the fetus which is why the results ar=
e so wide spread and also why the results vary among individuals.
For a number of years I kept records asking people with ferrets who have ne=
ural crest gentics markings to contact me when the ferrets died so that I c=
ould get a handle on life spans for them. This was NOT a scientific survey=
. At first I heard only of those who died young. Later people began writi=
ng to say that they wanted to be among the people who could tell me of aver=
age or long life-spans. Almost always these people wrote later to say that=
the ferrets had died young. Medical problems seem to develop at younger a=
ges, as well, especially malignancies (which may be due to Kit being an onc=
ogene since that name reflects not only the source of the mutation but also=
that it can imbue an increased vulnerability to a malignancy. The upshot =
is that unlike so many other markings these ferrets usually don't reach the=
ir 7th year. Only a handful of ferrets mentioned reached that amore averag=
e age, and only one who I heard of could be called very long lived (9 or ol=
der).
Notice that the markings are THROUGHOUT life, and that a blaze can roan int=
o a panda. If a ferret who was unmarked earlier roans as an adult that is =
NOT from neural crest genetics.
=
=