Please critique my comb genetics page

[The Chicken Lady]

Here is my comb genetics page I'm doing for BYC:
https://www.backyardchickens.com/web/viewblog.php?id=9280-Comb_Genetics

I'd love it if you genetics buffs would give it a read-through and see if you understand what the heck I'm talking about. If you see any major issues or problems with scientific vocabulary let me know. I'm not a scientist by trade so it's quite likely I screwed something up. I want it to be *right* so let me know what to fix.

Writing it was really tough, but I think I now know more about combs than I ever did before since I laid it all out.

(I'm still researching where the heck V-shaped combs and buttercup combs, etc., came from... That will likely be added later.)

Thanks!

 

[PeeperKeeper]

Mercy! That's a lot of thought written out. Brought back memories of my introduction to Mendelsohn's Sweet Pea crosses I had to memorize in biology!

I think I'll print it out and study it a little more...especially the part about single combed Sebrights. What I read of it was well explained and putting examples of certain breed crosses and outcomes is very helpful following all those PP,pp RR, and rr's.

What an endeaver!!

 

[wclawrence]

I will point out a few things. Hopefully I can help a little.

p/p does not necessarily mean that the "recessive gene p/p is present"
but rather it simply means that there is no P, which is pea comb. In other words, pp/rr simply means straight comb.

okay next point.
there are a few other (probably unnamed) genes associated with combs.
One is for size. If you look at some leghorns, they have massive combs like ax heads. and then look at fayoumi, they have fairly small combs. another thing to note is that, often, comb genetics are so close to other facial features that it can be hard to breed for two things on the same bird. FOr instance pea combs are usually accompanied by small wattles. And white lobes are more common on p/p/r/r birds than any other.

Third point
The buttercup gene and the V-comb gene _-*I THINK*-_ are really similar, if not the same thing.
I think it is a co-dominant gene, that is, one copy makes a pp/rr bird have a normal straight comb, except for a small buttercup in the rear of the comb, while 2 copies allow for the full buttercup to form. I think V-comb is what you get when you allow the buttercup gene to interact with something else (maybe another comb gene, maybe something else)
I do have good evidence for this.

I have the buttercup gene coming out in my flock of Phoenix, which have never had Sicilian Buttercup OR anything V-comb introduced into them. But they do have Grey Junglefowl in them (about 12%) and Ceylon Junglefowl too (also about (12%)
I theorize that, since the Grey's genetics call for a lot of points on the comb, and the Phoenix' genetics call for only 5, the comb has "decided" it wants 15 points, but has no room to do it in, so it splits into two combs to accommodate.

But that is just some redneck's take on it.
Take it how you will.


By the way you did a really good job. Keep up the good work!

 

[ginbart]

I wish you could have put pictures of the different combs. I just posted a topic to see if someone could show me the difference. That may help us newbe's. Thanks

 

[Blisschick]

Quote:
My chick is showing signs of having a buttercup comb -- I think. She's got 14 points total, with 6 on one side, 5 on the other, and 3 at the back. The father has Silkie, Modern Game, and EE on his side, and the mother is what I think is a Cochin mix. The mother's comb is small like a Cochin's. I don't know if the father had and buff Silkie in him, since he has one of those big ax-head combs you mentioned, but I'm guessing it's a possibility. Of the other chicks from them, so far I have a pea comb (? possibly another buttercup?) and a single comb. I have another hatching tonight, so it will be interesting to see what it has. This is the first time I've had it pop up in a mixed breed group.