polecats

[Crow 1]

At the risk of provoking Crow again, I don't think the situation with albinos in ferrets is quite as simple as in most other species.

 

It is just that droid As you probably know albinos have an autosomal recessive pattern of inheritance therefore are the only ferret colour you can look at and know for sure it's genetic make-up.

[stubby 175]

so crow, Im interested on the reason for asking if I was 100% sure on the parentage of mine, this albino thing is new to me

[droid 11]

At the risk of provoking Crow again, I don't think the situation with albinos in ferrets is quite as simple as in most other species.

 

It is just that droid As you probably know albinos have an autosomal recessive pattern of inheritance therefore are the only ferret colour you can look at and know for sure it's genetic make-up.

 

So how do you explain the relatively high incidence of albinism within ferrets?

[Crow 1]

It's simply because a lot of the polecat coloured ferrest are carrying the albino gene - ie. Pa as apposed to PP. They look the same until you breed off them!

[droid 11]

So if you mate albino with albino then you're guaranteed all albino kits?

Edited May 30, 2008 by droid

[Crow 1]

So if you mate albino with albino then you're guaranteed all albino kits?

 

Yes, no question about it. The albino gene (let's label it a) has an autosomal recessive pattern of inheritance meaning that two 'albino' genes are required to take effect. Therefore, mating an albino (aa) to another albino (aa) can only produce offspring of aa - there are no other genes 'in the pot' so to speak.

 

Polecat coloured ferrets can (for want of a better word) be 'true' in as much as they carry two polecat colouration genes (let's label it P). Mating two 'true' polecats to each other (PP x PP) will only produce polecat coloured ferrets.

 

However, the polecat colouring has an autosomal dominant pattern of inheritance therefore only one gene is required to take an effect. Therefore, a 'true' polecat (and I'm using the word 'true' in relation to it's colour genes not the animal in general) would look the same as a polecat coloured ferret carrying the albino gene. They both have the same Phenotype (physical looks) but their Genotype (genetic makeup) is very different. The 'true' polecat will be PP, the other will be Pa.

 

Mating a 'true' polecat (PP) to one carrying the albino gene (Pa) will always give polecat coloured offspring, but 50% (mathematically) would carry the albino gene.

 

Mating two polecats that carry the albino gene together (Pa x Pa) will give us 25% albinos and 75% polcat coloured. However, whilst that 75% will have the same Phenotype (looks), two-thirds will have the genotype Pa and the other third will have PP.

 

Mating a Pa polecat to an albino will give us (mathematically) 50% albinos and 50% polecat coloured (all carrying the albino gene).

 

You asked earlier why there are so many albinos - it's all down to the hidden gene in those polecat coloured

 

so crow, Im interested on the reason for asking if I was 100% sure on the parentage of mine, this albino thing is new to me

 

I was trying to work out the probable genotype of your ferrets, but as there seems to be some uncertainty about the matings then that is not possible - i.e on the jill side in one post you described her as "a last years polecat jill (silver/albino parents)" but in the next post as a "silver jill", whilst the hob could be "either a polecat or a silver"!

 

Crow

[Malt 379]

So the albino gene is like the gene that gives blue eyes in humans?

ie: Two people with brown eyes can have a child with blue eyes so long as they BOTH carry the recessive blue eye gene, but two people with blue eyes cannot have a baby with brown eyes.

[droid 11]

Cheers Crow.

 

You explained that well.

 

How would you describe the phenotype of the 'A' allele though?

[droid 11]

So the albino gene is like the gene that gives blue eyes in humans?

ie: Two people with brown eyes can have a child with blue eyes so long as they BOTH carry the recessive blue eye gene, but two people with blue eyes cannot have a baby with brown eyes.

 

As far as I'm aware, yes.

 

My excuse for getting this wrong is several pints of Pedigree....

[Crow 1]

So the albino gene is like the gene that gives blue eyes in humans? ie: Two people with brown eyes can have a child with blue eyes so long as they BOTH carry the recessive blue eye gene, but two people with blue eyes cannot have a baby with brown eyes.

 

I know absolutely nothing about eye colour in humans, but if the theory ties in and that is how you wish to understand it then go for it

 

How would you describe the phenotype of the 'A' allele though?

 

As you will know, when we use the term 'gene' to describe inheritance of the albino or polecat colour as I have above (i.e. "therefore only one gene is required to take an effect") we are actually using the term 'gene' in the wrong context. The gene actually holds two alleles, one being inherited from each parent and it is these that dictate colour, but using the term allele always brings the question 'I thought it was down to genes??' so it's easier to use the term 'gene'.

 

Also, when we label the polecat carrying the albino 'gene' (or to be correct allele) as Pa that again is actually technically incorrect as it doesn't follow genetic referencing practice. What we should do is give the dominant allele the capital of the recessive allele. In this case we should label the polecat carrying the albino allele (more commonly and erroneously called gene) as Aa. This makes it bloody confusing when you try to explain that a polecat PP mated to an albino aa gives an entire litter of kits that all look like polecats but have the genotype Aa Far easier to understand if we use the reference Pa

 

Of course, if we were in the middle of accurate records and were dealing with an F1 or F2 generation then it would make more sense, but on here I'll stick to using the term Pa - and the term gene in place of allele too!

 

So, to your question "How would you describe the phenotype of the 'A' allele" my answer would be 'polecat coloured if either of the parents was polecat coloured'.

 

Crow

[stubby 175]

so crow, Im interested on the reason for asking if I was 100% sure on the parentage of mine, this albino thing is new to me

 

I was trying to work out the probable genotype of your ferrets, but as there seems to be some uncertainty about the matings then that is not possible - i.e on the jill side in one post you described her as "a last years polecat jill (silver/albino parents)" but in the next post as a "silver jill", whilst the hob could be "either a polecat or a silver"!

 

 

 

either its my typing, or your reading it wrong, your quoting two differnt matings that I described, not one pair,

 

but from reading your earlier post, both of my polecat jills from last year, must be split/carring the albino gene, and the sandie hob that was paired with them (unknown parentage) must be carrying it also, as they have both produced albino kitts

 

"the silver jill" was an unplanned mating, and could have been covered by either another silver or a polecat, there are no albino's in the 12 kitts produced, but the parents were bred from the same original albino hob, therefore none of them can be split/carries of the albino gene,

[Sighthound 49]

-The trouble with this topic is that their are only a very few 'cast iron' rules concerning this type of genetics. I agree Albino X albino = all albino. or pure polecat to pure polecat = all polecat.

As I've said before Crow the genetics you are using are simple Mendelian genetics

 

http://www.ndsu.nodak.edu/instruct/mcclean...del/mendel1.htm

 

These relate to simple plants, in his case pea plants.

 

Ferrets are obviously far more complicated and although it's fun tryimg to predict colour type it's not really possible,

it also does not explain, sandy, silvers, blacks or black eyed whites, as well as shading ie dark polecat light polecat.

 

Also the ratios you use are only a theoretical prediction,

 

Mating two polecats that carry the albino gene together (Pa x Pa) will give us 25% albinos and 75% polcat coloured. However, whilst that 75% will have the same Phenotype (looks), two-thirds will have the genotype Pa and the other third will have PP.

 

It is quite possible that mating Pa to Pa will result in the whole litter being PP or even all albino

 

Remember that at one time ALL ferrets were pure polecat ( ie wild), so if we accept that then we must accept thay were obviously all PP so in that case using Mendelian genetics we could never get albinos, sivers, etc.

The reason we do is gene mutation - now thats a whole new subject

[droid 11]

Also the ratios you use are only a theoretical prediction,

 

Mating two polecats that carry the albino gene together (Pa x Pa) will give us 25% albinos and 75% polcat coloured. However, whilst that 75% will have the same Phenotype (looks), two-thirds will have the genotype Pa and the other third will have PP.

 

It is quite possible that mating Pa to Pa will result in the whole litter being PP or even all albino.

 

Thats because what you get depends on chance, which is why I got told off for hypothesising from a single example. Over many examples Mendelian ratios will hold true, if colour in ferrets is based on a single gene.

 

Albinism is a pretty simple mutation. It's happened in many species, including humans.

Edited June 1, 2008 by droid

[Sighthound 49]

Also the ratios you use are only a theoretical prediction,

 

Mating two polecats that carry the albino gene together (Pa x Pa) will give us 25% albinos and 75% polcat coloured. However, whilst that 75% will have the same Phenotype (looks), two-thirds will have the genotype Pa and the other third will have PP.

 

It is quite possible that mating Pa to Pa will result in the whole litter being PP or even all albino.

 

Thats because what you get depends on chance, which is why I got told off for hypothesising from a single example. Over many examples Mendelian ratios will hold true, if colour in ferrets is based on a single gene.

 

 

 

true - do we know however that colour is based on a single gene though?

[droid 11]

Which is why I asked about albino*albino crosses.