Leucistic Blue-tongue Skinks

[euan]

Not glowing per se but rather a very pure white, almost matt.

 

[richardsc]

bapi i still say hypos,but thats fine,there still stunners mate,and look ten times better than albino easterns in my books,thats what erks me with morphs,people make there own names up for different morphs,confuses the be jesus out of me,what percentage of bubs in a litter have the paleness,or do they develop it from birth

 

[richardsc]

ive seen pics of hypo northerns but never as pale as bapis ones

 

[NCHERPS]

. On a side note the terms T+ and T- are used frequently but they are terms that to the best of my knowledge have not been proven.

:shock:
I think you will find that they have been proven.
Or have I just misunderstood what you were trying to say!

Neil

 

[BROWNS]

I have a friend who accidently ran over a true leucistic BTS and it was almost see through,you could even see the venom glands through the skin.It died on the way to the vet and is now in a jar however more have been sighted in the same area.

A leucistic animal has no pigment at all and can be pure white with black or blue eyes such as the macs fond in Townsville area handed in to National Parks and can also be a pikish see through colour like the BTS i just mentioned and i will get a photo of it as son as i can find it.

A leucistic animal shold look like this ball python!!None of the blue togues posted have been true leucistics but stunning animals in their own right!

 

[Bluie]

So Browns what would you call the bluies that bapi has photos of hypo or not.

 

[BROWNS]

Well it's definitely not a leucistic seeing as there is a slight pattern and if it is hypomelanistic it's the best example you'll get as there is no black whatsoever other than the pupil and hypomelanistic just means lacking in black not no black at all but having no black at all is what i guess i'd call a perfect hypomelanistic animal.Would love to see it in the flesh!!

 

[Australis]

Hi Babi,

Have you established what the pattern of inheritance is?
In the ones ive seen from normal northern parents it was
around 50% whiteys and 50% normals....
lending to the idea of simple recessive, but im not too
crash hot with genetics..


Matt

 

[euan]

:shock:
I think you will find that they have been proven.
Or have I just misunderstood what you were trying to say!

Neil

T+ and T- was a term brought to herpetoculture by Dave Barker, well at least he was the first I heard using the terms.
People use the terms but not always in the possibly correct manner. Plus to my knowledge nobody has proven actually that any of the reptiles termed such, are actually Tyrosine "adjusted" for want of a better phrase.

 

[Bapi]

It is autosomal recessive. suffucient numbers have been bred to confirm that - Normal X mutant = hets(normal looking but carry the gene)
Het X het = 25 % mutant, 25% normal & 50% hets
mutant X mutant = 100% mutant
etc etc

The complication with naming mutations is that different mutations can look the same and the same mutation can look different. both between individuals & between species. As an example the white faced cockatiel and the sky blue budgie are the same mutations but look totally different. This is why we are having this discussion.


hypomelanistic is only the same as dilute in mammals where all skin pigments are descended from melanin. In birds and reptiles yellows & reds are not from the same chemical pathways so a hypomelanistic or amelanistic can be quite brightly coloured in these groups so they are not neccessarily diluted.

In this mutation all groups of pigments are greatly reduced (blacks, yellows & reds) so I guess we should call them hypopigmented so everyone can be happy

I would still group this mutation in the leucisitc group since it affects all pigment classes not just melanin. All mutations are is "stuff ups" along a biochemical pathway. The "true leucistics" are I suspect are stuff ups higher in the pathway than this one. Similar to T+ and T- albinos which are stuff ups either side of a particular product (tyrosinase) in the melanin pathway. If you want more discussion on this check out the albino allelles in cats.

Anyway i think the current Wikipaedia article on leucism explains it well and I quote

"Leucism is a condition characterized by reduced pigmentation in animals. Unlike albinism, it is caused by a reduction in all types of skin pigment, not just melanin.
Leucism is a general term for the phenotype resulting from defects in pigment cell differentiation and/or migration from the neural crest to skin, hair or feathers during development. This results in either the entire surface (if all pigment cells fail to develop) or patches of body surface (if only a subset are defective) having a lack of cells capable of making pigment.
Since all pigment cell-types differentiate from the same multipotent precursor cell-type, leucism can cause the reduction in all types of pigment. This is in contrast to albinism, for which leucism is often mistaken. Albinism results in the reduction of melanin production only, though the melanocyte (or melanophore) is still present. Thus in species that have other pigment cell-types, for example xanthophores, albinos are not entirely white, but instead display a pale yellow colour.
More common than a complete absence of pigment cells is localized or incomplete hypopigmentation, resulting in irregular patches of white on an animal that otherwise has normal colouring and patterning. This partial leucism is known as a "pied" or "piebald" effect; and the ratio of white to normal-coloured skin can vary considerably not only between generations, but between different offspring from the same parents, and even between members of the same litter. This is notable in horses, the urban crow[1] and the ball python[2] but is also found in many other species. In contrast, albinism always affects the entire animal.
A further difference between albinism and leucism is in eye colour. Due to the lack of melanin production in both the retinal pigmented epithelium (RPE) and iris, albinos typically have red eyes due to the underlying blood vessels showing through. In contrast, leucistic animals have normally coloured eyes. This is because the melanocytes of the RPE are not derived from the neural crest, instead an outpouching of the neural tube generates the optic cup which, in turn, forms the retina. As these cells are from an independent developmental origin, they are typically unaffected by the genetic cause of leucism.
Genes that, when mutated, can cause leucism include, c-kit [3], mitf [4] and ednrb [5]"

 

[Pike01]

What are these ones,hypo's?

 

[Saz]

Here's a vibrant bluey to add to the mix.

Lovely to see some more potential morphs getting about. Yours look like hypos to me Pike.

Blueys are just awesome critters, whatever the colour.

 

[NCHERPS]

T+ and T- was a term brought to herpetoculture by Dave Barker, well at least he was the first I heard using the terms.
People use the terms but not always in the possibly correct manner. Plus to my knowledge nobody has proven actually that any of the reptiles termed such, are actually Tyrosine "adjusted" for want of a better phrase.

Euan,

The terms T+ and T- used to describe the two conditions effecting the animals and there abilties to synthesis Tyrosinase have been around for a long time and are considered valid for most fauna, reptiles included.
I have never heard anyone in herpetoculture dispute the existence of these animals and the conditions they are afflicted with.

I agree with you on one thing though, many people make judgements and use terms to describe animals without seeing them in the flesh, but when you come onto a reptile forum and someone asks for your opinion, you will give it with the best available information to hand.

Neil

 

[Retic]

Pike, yes I would say they are the same as the ones Bapi posted, hypo.

 

[Bluie]

Pike1 are they northerns

 

[Frozenmouse]

i still say the ones bapti posted are luecistic.
hypo melanistic does not desrcibe them fully and there are varying degrees of luecism just because they are not "glowing white" or "see through" does not prove they are not luecistic.
there is a few accounts of luecistic humans and one of them had red hair,still luecistic tho.
i have seen a luecistic galah which still had about 20% normal feathers .
So having some slight patterning does not discount the fact that they are luecistic.

 

[euan]

Euan,

The terms T+ and T- used to describe the two conditions effecting the animals and there abilties to synthesis Tyrosinase have been around for a long time and are considered valid for most fauna, reptiles included.
I have never heard anyone in herpetoculture dispute the existence of these animals and the conditions they are afflicted with.

I agree with you on one thing though, many people make judgements and use terms to describe animals without seeing them in the flesh, but when you come onto a reptile forum and someone asks for your opinion, you will give it with the best available information to hand.

Neil

I well understand the terminology, the term was first used in herpetoculture by Dave Barker, when Bob Clark hatched out a few different phenotypes from his albino retics. It was approx 1995 at the Orlando Reptile Expo when I first heard it. If my vague memory is holding up that was the year Bob bred them. At the 1991 Expo he exhibited the original male albino retic, which was not volontarily feeding at the time. Since then it has been used with greater frequency.
If you have never heard T- or T+ terminology being disputed then you have not been in a big enough circle of herpetoculture
To the best of my knowledge there has never been a scientific paper showing ANY of the lines labelled as T- or T+ in reptiles is actuality or not. It has all been supposition due to appearances i.e the phenotype. Can you provide me with a paper where lab work has been do to show either is true ??? I would be very interested in a copy.

From "common usage" of the term leusistic in regards to reptiles the blue tongues pictured do not conform. I am aware in different spp different mutations can manifest themselves in different visual ways. So far the leusistic reptiles I have seen and held were Texas Ratsnake, Ball Python ( as well as partial), Alligator, Nile Monitor, Monocled Cobra, a few more which I can not think of at the moment, one of the Pituophis. Anyway I digess, what I am saying is so far ALL of the leusistic reptiles that I know of exhibited a complete lack of pigment in the skin ( except the Pied Balls, which was normal patterned patches combined with leusistic patterns ) which these Blue Tongues do not. So from "common usage" of the term they do not conform.
There is a bird guy here who turned a number of mutation names upside down when he started looking at actual mutation compared to common usage names. Would be interesting to find out from him his thoughts.
I would be interested to see a photo of a leusistic Galah, PM me one if possible.
Time for dinner Bye.

 

[Reptile City]

WoW Saz!
Thats a very nice Bluey.:shock:
So are some of the hypo posted too!
Heres one I had but sold it a year ago.:cry:

Jason

 

[scorps]

bump (interested to see how this goes)

 

[NCHERPS]

To the best of my knowledge there has never been a scientific paper showing ANY of the lines labelled as T- or T+ in reptiles is actuality or not. It has all been supposition due to appearances i.e the phenotype. Can you provide me with a paper where lab work has been do to show either is true ??? I would be very interested in a copy.

Euan,


You are just as aware as I am that scientific papers aren't in abundance where albino's and other reptile morph's etc are concerned. Researchers tend to concentrate on wild types rather than putting valuable research dollars into establishing whether David Barker has correctly labeled something as T+ and T-.
The fact remains that just because something might not yet of had a scientific paper(in relation to pythons) written about it doesn't mean he and many others aren't correct in their assumptions.
I seem to remember some time ago talk in the Leopard gecko community there was talk about undertaking Tyrosinase tests to establish what was what. I think there was also some work done on Rat snakes also.

As far as having not been in a big enough circle of herpetoculture, well maybe just a case of not being in a circle of herpetoculture that encompasses your views. There are many big name breeders that go along with the T+ and T- labels two of which you have mentioned yourself and countless others to boot.

What would you classify the animals as that are currently labeled as T+ and T-?
What would you label the conditions if not that described?

At the end of the day, people will always have different views and takes on the subject, mine is as I have expressed as it makes sense to me.

Cheers Neil