ISO Chicken Genetics 101 - So Confused

[FayoumisFreak]

I am very interested and intrigued with all of these breeding projects happening. however, I don't understand the majority of this 'genetics' talk. I am not not sure what the complex symbols and lettering represent. Could somebody point me towards an article, or just kinda give me the basic info needed to understand some of this complex genetics? I'm very interesting in breeding and genetics, and would love to find out more.
Thank you for reading and/or responding!

 

[LilJoe]

Following... I don't understand it much either... taking genetics next year so

 

[ve]

www.edelras.nl/chickengenetics/mutations1.html
Check this page. It has very good beginners information. There are 3 pages

 

[Backwoods Bntms]

There is a book available at amazon called "A Introduction To Color Forms of the Domestic Fowl" by Brian Reeder that explains the basics really well and is easy to understand. It even goes through the 5 e-locuses and lists the varieties found on them and gives the genes that make up each variety.

 

[FayoumisFreak]

Thank you so much for all of you help!

 

[sylviethecochin]

Something that really should help:

http://www.edelras.nl/chickengenetics/theory.html

It's a good basic introduction to the vocabulary, and there are other sections of the site. If you have time and patience and can sit down with a dictionary and a notebook, it gives you a really good introduction. Also, it's free, which is great.

 

[The Moonshiner]

If I could just type away and help you I would.
There's a lot going on with chicken genetics and I wouldn't even know where to start.
The fast track would be researching and reading everything you can.
Take everything with a grain of salt and consider the source.
Compare info from different sources and soon things will start making sense. Its overwhelming to try to jump in and learn ever thing at once.
Take it step by step. one thing will lead to another to another and so on.
Maybe at some point you can pick a project and dive in. That's when the fun starts.
Good luck. Hoping to be reading about your projects here sometime soon.

 

[Backwoods Bntms]

I understand what The Moonshiner is saying, you can't learn this all at once. But still it is nice to have a starting point, I remember how it was when I started looking at all the info and symbols. So I will try and get you started. This will be a simplified version, covering color only, so if I over simplify don't holler at me.
First the symbols are simply pairs of genes that exist in a bird. Example s+/s+ simply means two copies of gold. s+ means gold, makes no sense already, why not g? There are only two choices for this location gold or silver, the lower case s means not Silver (S). The genes written in lower case are recessive meaning the trait will show if it is doubled up, mo/mo will be mottled, mo/Mo will not. The genes are listed with descriptions alot of places so I wont go through them.
The next thing that is a little confusing is the e-Locus, which is the first pair of genes listed in the notation. This is like the model of chicken that determines the paint scheme of the bird. There are only 5 base models. It all started with the red jungle fowl so we will start there.
Duckwing --- e+/e+ s+/s+ this is the notation for a black breasted red. By adding other genes to this basic bird other colors can be made, all the duckwing colors, quail, spangled and the silver varieties of those colors.
That is a start if it helps comment and I will do some more.

 

[nicalandia]

I understand what The Moonshiner is saying, you can't learn this all at once. But still it is nice to have a starting point, I remember how it was when I started looking at all the info and symbols. So I will try and get you started. This will be a simplified version, covering color only, so if I over simplify don't holler at me.
First the symbols are simply pairs of genes that exist in a bird. Example s+/s+ simply means two copies of gold. s+ means gold, makes no sense already, why not g? There are only two choices for this location gold or silver, the lower case s means not Silver (S). The genes written in lower case are recessive meaning the trait will show if it is doubled up, mo/mo will be mottled, mo/Mo will not.

I agree with you and I would like to commend you for a very good example, I would just add that the + sign(as in E/e+ or Mo+/mo) is to indicate if it's wildtype(comes directly from Red Jungle Fowl) Also the placements of the genes, for Example Mo+/mo, placing the Capital and dominant gene first in the allelic pair(Mo+/mo instead of mo/Mo is the accepted nomenclature)

Thanks

 

[speckledhen]

Marvin, nicalandia, knows that I have a mental block when it comes to gene designations, I admit that! And he's always been nice enough over the many years we've encountered each other to answer my questions with humility and kindness, which I've always appreciated! I know what I have to know for the birds I breed, the Barred Rocks and the Partridge Brahmas, used to for the mille fleur and porcelain Belgian D'anvers, but they don't lay and I'm letting them die out. I've learned things from weird stuff that popped up on the farm here and there like the one freak of nature that hatched from a BBS Ameraucana flock, but looks like a Sumatra hen. I have found no real reason to learn anything other than the plain language stuff, at least for me.

However, I want to interject into this conversation that not everything with genetics is "textbook" black and white. Unexpected occurrences can happen, genes can play tricks you never knew were possible. Even some of the experts, self-styled wanna-be's or those with actual higher education in poultry science, would argue with me on a few points that I know from my own first-hand experience. For example, I know for a fact that on very rare occasions, a bird can be the carrier of two dwarf genes. Yes, two in one bird. Most never have experience with dwarfism in their flocks, do not even know that there are several types of dwarfism. How do I know that two copies can exist in one bird? Genetic testing on my own line of Delawares.

Years ago, a friend who lived in Oregon at the time, hatched two daughters out of my Delaware flock, one very large and one slightly smaller-bodied. I subsequently learned that two odd chicks had hatched from eggs I sent to someone in other states. This friend in Oregon mentioned the dwarf gene to her veterinarian at the time, who coincidentally, and lucky for us, was doing a study on dwarfism in poultry at the time. With her permission, he drew blood from both hens and did genetic testing for his study. The smaller-bodied hen carried NO dwarf gene. The larger bodied hen, even named Fattie for her wide girth, carried TWO copies of the gene. He told us that most of his colleagues did not believe it possible, however, this hen should never reproduce because every chick would be a dwarf.

This type of dwarfism is thyrogenous, related to the thyroid gland, a semi-lethal gene that does not allow the bird to live to full maturity. I wrote an article, with photos, for BYC, chronicling my experience with this type of dwarfism I'll link below. Just wanted to interject that I have been told by some that this or that "cannot" happen, but I've seen it with my own two eyes. We do not know all we think we know about genes in poultry, or anything else for that matter. The double dwarf gene carrier hen was a prime example. If it can happen with a dwarf gene, can it happen with other genes? Who knows? I never say never, no matter what anyone swears can't happen.

Just when you thought learning the alphabet-soup gene designations were hard, this crazy stuff happens and throws everything you think you know right out the window.

https://www.backyardchickens.com/articles/thyrogenous-dwarfism-in-poultry.72684/