Genetics of Chicken Extremes book

This book completes the whole story of the chicken genes. All genes next to the colour genes in chickens, encountered in hobby breeding. The influence of feather colour genes on other body parts are discussed too.
The word ‘extremes’ refers to everything different from the standard chicken: Red Jungle Fowl. Or, all genes written without a ‘+’ behind its abbreviation.

Genetics of Chicken Colours and Genetics of Chicken Extremes are together the most complete work ever in words and photos and schemes on the genetics of fancy breeds.


These books are the state of the art descriptions of the genetics and the actions of genes on both sexes which every serious breeder should know, as they are the basic genes that make breeds look the way they do.

If you plan to use another breed for borrowing a gene in your project, Genetics of the Chicken Extremes is your guide, together with the Chicken Colours book. Less chicks to rehome, no more gambling, no more money and room wasted or too full pens, so less diseases because you KNOW what you are doing. Talk to other breeders in the same ‘language’ and no confusion anymore where you are talking about.

Special permission from the Roslin Institute Edinburgh, to write more about the gynandromorph chickens.
A chapter on selection of hatching eggs, a chick in breech
and much more in Genetics of Chicken Extremes.

Very easy to understand explanations. Explanation how inheritance works is in the Colours book, Extremes is all about the genes of combs, toes, beards, crest & tassel, bantam and large, skin and leg colours etc. and their actions and expressions when impure. Also included are mixes (projects) of features like mixed toes, combs, beards, crests, combs etc.

When you use another breed for one trait and you want to breed back to your original breed you will encounter some utterly weird things. Since I’ve done that myself several times, and documented it, there is a lot of experience packed between the covers.

Not unimportant, lethal genes are discussed and the stages of embryo development during incubation.

In Genetics of Chicken Extremes much on odd things like wry hips and spine, wry tail and tail shapes.

On semi-lethal genes like Cornish lethal, thick legs and splay legs, the leg colours and all ins and outs about them.

The leg feathers, always a very confusing thing happening, if you want them, they disappear and if you want to get rid of them, they pop up for years. Dead eggs, just only early development, lethal genes in embryos and how they look. More on disease resistance by selective breeding.

Mosaic, half the chicken displays a trait and the other half not, what about the XY axis, what happens when things run out of control? The by-effects of pea comb, all pleiotrophic effects of pea comb illustrated fully in real chickens.

Sometimes we use genes that are not so good for chickens, in Genetics of Chicken Extremes is explained what genes and why. The book is split up in chicken parts, each body part is discussed separately and what genes have influence on a specific part.

In the book you find schemes of genes and how they behave pure (homozygous) and impure (heterozygous) on male and female. You will learn what genes affect what parts and that there are so called multi-allelic traits, so there is no gene that determines the width of a tail or the length of legs and multiple genes are responsible for a lot of traits. The book starts with history and how the chickens went from ‘birds’ to classified breeds. This is necessary for understanding. You see breeds developed over the centuries and decades, depending on preferred selection at the time.

If you want to know what genes are discussed, see the content pages…


200 pages, 500+ fc photos

The book Genetics of chicken Extremes costs €75.
• Shipping costs Europe: €15, total €90

• Shipping costs World: €23.50, total €98.50
The books are sent by registered mail.

I will sign your book with soft pencil, so you can see it is not a printed signature.

World (USA, Australia etc.)
Genetics of chicken Extremes, incl. shipping €98.50)

Europe & UK
Genetics of chicken Extremes, incl. shipping €90

Consider using iban/bic bank payment when you are in €-zone. Email me for bank payment. When you are in the United States of America, I have a USD {$) normal bank account at Wise, I can send you a pay-link.

If you want to order both Genetics books, check out Book Combis