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this was originally at the end of the (long--sorry!) post below int he thread about extreme hypos. I figured it might prompt more discussion if pulled out and presented on its own, and that's what i'm doing here. it would be best to read this, i think, after reading my 11/5 post in the extreme hypo thread)

And this last mind-bending thought: there COULD be two diff hypo morphs EACH of which reduces melanin to the same degree. Suppose the Loves produced the first, and that a second, genetically different but visually similar one appeared more recently. Nobody'd notice, right? At least, until they bred two hypos together and didn't get hypos. BUT: what if the new morph occurred in mike falcon's group so all are "regular" hypos....breeding them together you'd still get all hypos so nobody would notice anything odd--EXCEPT for the occasional extremely light animal, which might be the result of combining the effects of two similar hypo morphs (if they each reduce melanin an average 35%, then babies showing BOTH morphs would have melanin reduced 70%. And those are averages...a double morph baby having better than average reduction could show only 10% of the melanin, for ex. (can this theory account for mike alvarez' reported experience of breeding extreme x extreme and getting 6 babies, 5 of which were obviously extremes and one of which did not appear to be so? maybe.)

peace
terry

As of right now I don't think there is enough evidence to say for sure if there are differant "lines" (genetically) of hypos in hondos or say pyros for that matter. I think there have been many terms thrown out there but as I said in a reply to Jeff our finite minds sometimes don't let us see the whole picture. Are we looking at a combination of effects from MANY genes that control pattern, pigment, scale development all of which are underlying to the hypo-M gene but cause a variation in phenotype. Are we seeing variations in single hypo-M genes that are only turned on when in a homozygous state but have "dominant control" over its counter part in the time in which melanin production is turned off? Correct me if I'am wrong but all the extreme hypos and super hypos for that matter have red or deep ruby eyes. I believe all snakes have red eyes in early stages of development only to have melanin introduced later to manifest black eyes. If melanin production is turned off eary in development it never gets to the eyes and you have a very faded red eyed hypo-M animal. If through succesive breeding you pair two animals that share similar genetics in regard to melanin control AND the aforementioned traits you could produce extreme hypos. Because of the multiple genes for other traits interacting those same extreme animals could produce non-extreme offspring but they would be hypo nontheless. I presume that the 1 out of 6 that was'nt extreme was at least hypo?? Let me end by saying I am in no way saying this is whats happening but just my best effort to get in words whats rattling around in my head and get some thoughts out there. Thanks Terry for the thread and I will look forward to more discussion!

Matt Woodhall

good thoughts, matt. i'll need to re-read & think about them more. you've already prompted a couple thoughts here:

re: pyro hypos, didn't jeff breed one x the other and get no hypos? and since each of the hypothetical two types (barczyk, sentz) have bred true as recessives to the best of my knowledge, that hypoB X hypoS pairing producing no hypos wouldn't be possible if there aren't two diff morphs, or alleles, would it?

(with the hondos, on the other hand, the extremes appeared from regular hypo breedings. so even if there ARE two diff morphs, or even if extreme is NOT a simple recessive but a look derived from multiple gene interaction, then it's still logical all the babies would be hypos (as they were, you're correct in your assumption). It's as if the first hypos emerged out of an albino breeding pair (a highly unlikely event, i'll concede, but hypothetically stick with me on this for a minute) ...in that case, even if there were slight diff looks between albinos and hybinos, it would take some pretty well-thought-out pairings before you could isolate the hypo from the albino. Hope I said that in a logical way...but that, i think, indicates a factor complicating our gaining better insights into the nature of the "extreme" hypo.

terry

He mentioned there seemed to be 3 phenotypes which I thought would be conveniently genetic.I have had my thoughts out here on the EXTREME hypos(lavender albino?)before....I just think they have to be different.Jeff

>re: pyro hypos, didn't jeff breed one x the other and get no hypos? and since each of the hypothetical two types (barczyk, sentz) have bred true as recessives to the best of my knowledge, that hypoB X hypoS pairing producing no hypos wouldn't be possible if there aren't two diff morphs, or alleles, would it?

Getting no hypos from this type of mating would prove that the two mutants are independent and not alleles.

IMHO, the most likely hypothesis for the extremes is the two independent mutants acting in combination. When I was working in a breeding colony of ringneck doves, we had blonds and ivories that were both lighter than the normal doves. Combining blond and ivory produced birds that were lighter in color than either blond or ivory.

I'd really like to see someone take a good look through a microscope at various mutant snakes' skin. The melanin pigment cells in the mutants might have different shapes than the normal melanin pigment cells. And the pigment granules in the cells might have different size, shape, density, or number. Or the melanin pigment cells might simply be less efficient than normal at producing tyrosinase.

Theorizing won't get us anywhere unless somebody tests the ideas. We need data most of all.

Paul Hollander

First of all Terry ALL pyro breeding thus far to my knowledge between the two possible hypo lines has been done with hets and hets to homo animals. No homo BHB X homo 'Sentz' has been done. Until that pairing has been done I think we are jumping ahaed on assumptions. Jeff's Het I might add has not yet been proven to be het for either hypo line. Jeff's breeding was between his hypo Sentz female and a 100% het/BHB but that het male is yet to father a hypo animal of any kind. The other pairing was a het X het by Mark Petros yeilding eight babies and no hypos but I don't think both those animals have been completely proven either.
On the hondo topic referring to the hybino the albino gene would still act on its own and the variance within the hypos would'nt be directly seen but would nontheless effect that same portion of the animal as well as the other gene pool within that same animal within that portion of the animal( if that makes sense?). Therefore a hybino would produce albinos and a variation of hypos comparable to what genes it may carry which would be the same as just the hypo animal. Again I think we are talking about MANY pieces of genetic material that fall within the control of the hypo-M gene when it is present.
Just as a side thought. We humans technically have the possibilty thru meiosis to produce two differant gametes when the chromosomes split. 2 genetically differant sperm and 2 genetically differant eggs. But it is not that simple or everyone would look similair without much variance. Is what happens is that during meiosis genes that lay close to one another cross-over to the opposing chromosome. This may happen in thousands of places creating many differant sperm combinations and many differant egg combinations that now come together and create a uniquie individual. The genetic info never changes just the way in which they line up with the opposing gamete. Crossovers are the reason we get 1 out of 16 chance in a DH pairing that is homozygous. I hope I did'nt get way off track here but this is touch to convey on the forum. If two animals are similiar enough genetically then crossovers will not be as big of an effect. Is what I think IMO is the extremes are such animals in that their hypo-M control is very similiar if not the same within the area that controls the turning off of the melanin production. I could draw it and probably show my ideas better?? Anyway I gone on too long already, look forward to any comments.

Matt Woodhall