Quick genetics question

[sachman]

Hi all. I am not a genetics expert in birds but do work in the field of biology. Just wanted to confirm something a breeder told me regarding a pied cockatiel. He mated a Lutino male with a pied female. He said that all pied babies would be male. But I am not following that. Couldn't a pied female be produced? My thinking:
1. Pied is recessive and the Y chromosome does not carry color info. So the female is pied/-
2. Lutino is dominant (I think). FOr a pied chick to be hatched doesn't that mean the male is Lutino/pied? In which case he could contribute a pied to the females Y and produce a pied female.

I know I am missing something so any lesson or thorough web site on this would be great. Thanks!

Mike

 

[tka]

Birds don't have X and Y chromosomes like humans do.

Female birds are ZW chromosomes
Male birds have ZZ chromosomes

 

[sachman]

OK. But the question still holds though my nomenclature might be off. I think part of my mistake is that pied is not on the sex chromosome but rather is autosomal. Yet both lutino and pied are recessive. So I guess the question is what happens when a recessive sex-linked gene and an autosomal recessive gene are together in the same bird? Which one predominates? Just trying to figure how the breeder says all pied chicks must be male.

 

[Destiny]

Lutino is sex-linked recessive. Pied is autosomal recessive.

I think the breeder mis-spoke. There is no reason to believe all males would be pied. In fact, you are unlikely to get ANY pied offspring from that pairing.

Lutino male to pied female would make all females lutino. All male offspring would be split to lutino (but look normal). This is because the female only has the one Z gene, so sex linked traits are always expressed in females, if present. For a male bird, they need to inherit sex linked genes from both parents to express the trait. Since the female wasn't lutino, none of the boys would be lutino.

Since pied is autosomal recessive, all offspring would be be split to pied. None of the offspring would be visually pied, unless the male was split to pied. In which case, half the offspring would be pied, regardless of gender.

Unless the breeder has reason to believe that the male is split to pied, the most likely outcome of this pairing would be all GIRLS would be LUTINO and all boys would be NORMAL. No pied offspring at all.

It is worth noting, however, that since lutino masks pied expression, you wouldn't be able to tell if a lutino girl was also homozygous for Pied. They would just look lutino. The difference in genotype would only matter if you planned to breed the offspring.

 

[Destiny]

Long story short, since all the girls would be lutino, you could only SEE pied markings on one of the boys (and only if the father was able to contribute a second pied gene). But technically, all of the babies would be carrying at least one pied gene, since the mother is pied. She would pass on one pied gene to all of her babies.

I think the breeder was just getting a little lazy in his word choice. I would have flipped it around and talked about how all girls will be lutino, rather than saying any pied offspring would be male.

While it is technically true, it is understandably misleading. It only works because the lutino trait masks expression of pied markings. Pied is not a sex-linked trait. The pied genes are still present and could still be passed on the future offspring. You just would not see them expressed on a lutino bird.

 

[sachman]

Thanks for the responses. He did say that all females would be lutino and there were 2 in the brood. But there was also one pied and he said that had to be a male based on genetics. I guess the father was split to pied. In which case it still doesnt seem to me that the pied MUST be a make if I understand the responses correctly?

 

[sachman]

Thanks for the responses. He did say that all females would be lutino and there were 2 in the brood. But there was also one pied and he said that had to be a male based on genetics. I guess the father was split to pied. In which case it still doesnt seem to me that the pied MUST be a make if I understand the responses correctly?

Last sentence should say male not make....

 

[Destiny]

All the girls are lutino. So any non-lutino birds (normal or pied) must be boys. Lutino masks pied markings on the female birds, so they will just look lutino, even if they are actually Lutino and Pied.

It also occurs to me that the lutino father could be carrying two pied genes - you can't see pied marking on a lutino. If ALL male offspring were pied, then he might has two pied genes. If ANY of the boys are not pied (normal markings), then the father is split to pied. And, of course, if the father doesn't have any pied genes, NONE of the boys will be pied. Since we know there was at least one pied boy, the father has at least one pied gene. Was there any normal offspring? Any non-lutino birds that were not pied?

All of the girls will be lutino, so we won't be able to tell if they inherited one or two pied genes from their parents by just looking at them.

Of course, if you simply must know, you could breed the female lutino offspring to a pied male to find out if they are pied or split to pied. The male offspring of this pairing would be split to lutino. Females would not be lutino (unless your pied male was split to lutino). All offspring would either be pied or split to pied. If you get any non-pied offspring, the mother does not have two pied genes. If all offspring are pied, she might have two pied genes.

 

[Shezbug]

@Monica

 

[Monica]

@Destiny pretty much explained it.

Since the breeder said that pied offspring would be males, we can only gather from this pairing that dad is either split pied or is an actual pied. If any of the offspring are normal, then he is split pied. If all the non-lutino offspring are pied, then he's a lutino pied.

It may be possible to tell that a lutino hen is ALSO pied due to LACK OF any baring or spots on the wings, tail and rump area of the hens. Pied is an anti-dimorphic mutation and can blur the lines between visual differences in genders. Pied feathers may also be a different color than the standard lutino feathers.


In short though....

Visual sex-linked mutation male paired with a hen of any other mutation

Equals all female offspring will be the same visual sex-linked mutation as the male

All male offspring will be whatever is "left over" (aka whatever is not the same mutation as the father)


If it helps to have this... (and if I'm awake enough to type this out correctly)


Lutino male x lutino female (not recommended pairing)
100% lutino offspring

Lutino male x normal female
100% normal males split lutino
100% lutino females

Normal male x lutino female
100% normal males split lutino
100% normal females

Normal male split lutino x normal female
50% normal males split lutino
50% normal males
50% lutino females
50% normal females

Normal male spilt lutino x lutino female
50% lutino males
50% normal males split lutino
50% lutino females
50% normal females

 

[Tink65]

Hi! I have a lutino female and a cinnamon pied male. They just hatched a little one 10 days ago... any way I could know what he/ she will be? Pics attached

 

[Monica]

Your hen appears to possibly be either a cinnamon lutino or another mutation - do you have photos with the natural light on her?

Chick is likely cinnamon at minimum