colour question

[poisondizzy]

I have been asked by a friend of mine to find out as much as i can about this ...

she has a grey mare .. one solid parent one grey ...
going to a homozygous coloured stallion .....
what are the chances of the foal greying out ...

also a bay mare .. again , one solid one grey parent ..
going to the same stallion .....

both mares in most generations back have one solid , one grey parent

she's been told by the stallion owner that the chances are they will grey ...

now me being as thick as i am , thought if he was homozygous he would throw colour whatever :confused: :confused: :confused: very :confused:

[Mehitabel]

he will throw colour whatever, but grey 'sits on top' of he colour. so in the first instance, baby will 100% be born coloured, but mum gives a 50% chance of greying out on top of it. so the beautiful splodges will eventually be hidden. 50% because mum is heterozygous grey, as she only has one grey parent. so she might pass on her grey, or she might not.

the second mare won't have a grey foal. if she is not grey herself, she can't pass it on, as it is dominant so can't skip a generation. if she had the grey gene she'd be grey herself, so the splodges are safe there!

[poisondizzy]

he will throw colour whatever, but grey 'sits on top' of he colour. so in the first instance, baby will 100% be born coloured, but mum gives a 50% chance of greying out on top of it. so the beautiful splodges will eventually be hidden. 50% because mum is heterozygous grey, as she only has one grey parent. so she might pass on her grey, or she might not.

the second mare won't have a grey foal. if she is not grey herself, she can't pass it on, as it is dominant so can't skip a generation. if she had the grey gene she'd be grey herself, so the splodges are safe there!

Thank you .... so at least they bay will quarentee a coloured ... she put the mares to this stallion in the belief that both would stay coloured , but was then told different , so at least i can pass on what you have told me ..
thanks again
sally

[Mehitabel]

yep - bay will definitely throw a splodgy one, and the grey one 50/50 as to whether it'll stay splodgy or go grey.

if she wants any reciprocal 'don't go grey' vibes, let me know! petal has a bun in the oven (hopefully, came back from stud on saturday) that i am hoping will stay bay!

[poisondizzy]

friends went of yesterday , so keeping fingers crossed ...
wish we didn't have to wait so long for foals to arrive .. :)