Introduction:

We don't claim ownership or originality for the genetics information which follows.  It is the product of significant non-avian genetics knowledge coupled with considerable input from folks on the "Genetics-Psittacine" list.  An attempt has been made to simplify much of the scientific lingo and produce an accurate and understandable description of Quaker genetics for the average reader.  We have found the online Quaker community to be free with "inside" information to us as we started our breeding program, and hope this can be of some help to those without a depth of genetics understanding.  We welcome any and all feedback which may help these pages become more accurate and informative.  Please drop us an email if you have any suggestions.

For those of you well versed in the basics of avian genetics, feel free to jump right to the more in-depth autosomal and sex-linked discussions.  If you're a pro with genetic notation, go right to the genetics tables where you can predict the genetic make-up of offspring for any of the 54 possible parental combinations of the green, blue, and pallid traits.  With these tables you can predict the inheritance of the Blue, Pallid (Dark-Eyed Cinnamon), Cinnamon (Red-Eyed Cinnamon), and Lutino traits as well as almost any combination thereof.  The inheritance patterns of the emerging Yellow and Pied mutations are less understood at this point.  For those of you in need of a quick avian genetics refresher course, read on.

Color:

To understand the inheritance of genetic color mutations, one must first understand the basics of why colors occur.  In most parrots, including Quakers, there are 2 pigments at work.  The first is a yellow pigment called psittacin. (sit'-uh-sin)  It appears yellow because it primarily reflects yellow light to our eyes.  The second is a black pigment called melanin which is also the sole pigment which occurs in humans.  This pigment appears black or gray in areas without feathers such as eyes, legs and toe nails.  However, the melanin in the feathers of a Quaker appears as a dark blue because the structure of the feathers bends and scatters the light in such a way that we see predominately dark blue light reflected.  The upshot of this is that both yellow and dark blue light are visible reflecting from Quaker feathers.  The combination of these two colors in the feathers is seen as dark green. (dark blue + yellow = dark green)  The combination of these pigments and colors are graphically depicted below.

It then follows that if the yellow pigment (psittacin) is suppressed by a genetic mutation, you would get a dark blue Quaker.  This is what we call a "Blue" Quaker.

If the blue pigment (melanin) was suppressed, you would expect a yellow Quaker.  This is what is happening in the Lutino Quaker.  

So, it is easily seen that Blue Quakers and Lutino Quakers are exactly the opposite of each other.  Each has one of the pigments (melanin and psittacin) completely intact and one completely suppressed.  One just has the opposite pigment from the other.

The difference between a Pallid (Dark-Eyed Cinnamon) and a Cinnamon (Red-Eyed Cinnamon) and their mutations' effects on pigment are a bit more complex.  But, they both have to do with the fact that the black melanin pigment (seen as dark blue) is altered in appearance or quantity.

The best supposition of experienced mutation breeders currently is that the Pallid (Dark-Eyed Cinnamon) Quaker has a partial reduction in the amount of black melanin (seen as dark blue) pigment.  So, instead of a dark blue contribution from the melanin, only a light blue is present.  This results in the overall color of the Pallid Quaker being a lighter green or more pallid appearing bird.  Hence, the name "Pallid" is appropriate.

The case of the Cinnamon (Red Eyed Cinnamon) Quaker is somewhat different.  Just as in Cinnamon mutations of other species, the amount of melanin pigment is roughly the same.  However, one of the steps that converts the initially synthesized brown melanin to black melanin is blocked.  Since brown melanin is not as dark as black melanin, the blue color seen is lighter and similar to that of the Pallid (Dark Eyed Cinnamon) Quaker but carries a slightly brownish tone.  When this light brownish blue is added to the yellow, a cinnamon color results.

What we call a "Pallid Blue" is simply the result of the combination of the "blue" and "pallid" Quaker traits as shown in the examples above.  The yellow pigment is suppressed as with the Blue Quaker example AND the dark blue (melanin) pigment is partially suppressed to a light blue as in the Pallid example.  The result is that only a light blue color is seen in the Pallid Blue as depicted below.

What we call a "Cinnamon Blue" is simply the result of the combination of the "blue" and "cinnamon" Quaker traits as shown in the examples above.  The yellow pigment is suppressed as with the Blue Quaker example AND the dark blue (melanin) pigment is lightened with a brownish tone as in the Cinnamon example.  The result is that only a light brownish blue color is seen in the Cinnamon Blue as depicted below.

And, finally, if we combine the "Blue" and "Yellow" Quaker mutation traits in the 2nd and 3rd examples, a "White" Quaker would be expected.  This is illustrated below.

Keep in mind that this is an oversimplification of how things really work.  Specifically, melanin (which produces the blue color) is partially or completely suppressed in many different ways.  It can remain intact in the eyes, legs and feet in Dark-Eyed Yellow (Yellow), Dark-Eyed Cinnamon (Pallid) or Dark-Eyed White (White) types or it can be suppressed in these areas in their Red-Eyed Yellow (Lutino), Red-Eyed Cinnamon and Red-Eyed White (Albino) counterparts.  There are many other factors involved which affect various areas of the plumage differently and there are many other potential mutations (judging by other psittacines such as Ringnecks) that will emerge and complicate this picture.  However, it gives a beginner a starting point.

The Wildtype Concept:

Before getting into genetics and the notation involved, it is imperative that one understand the concept of a wildtype bird.  Simply put, the wildtype bird is the one we are used to seeing in the wild.  For the Quaker, this is a medium to dark green bird with a few dark blue flights and tail feathers and gray on the chest, cheeks and forehead.  We also expect this "normal" Quaker to have black eyes and nails, gray legs and feet and a pinkish bill.  Subspecies aside, virtually all wild Quakers fit these basic criteria.  These "wildtype" traits are the backdrop against which we will base the following genetic mutation discussion.  The key to the wildtype concept is this:  Any time a particular mutation being discussed is absent, it is assumed that the "normal" or "default" or "wildtype" appearance is present.

Basic Genetics:

Inside the nucleus of every cell in any animals body lies several pair of chromosomes.  In humans, there are 23 and in birds there are usually 6 to 10 pairs (depending on the species) as well as a number of "microsomes" which will be ignored in this discussion.  One pair of these chromosomes are "sex" chromosomes which we'll deal with later.

Chromosomes are made up of genes linked end to end.  It is the gene that is the base unit for genetics.  Each gene has a specific place on a given chromosome and is responsible for a specific trait such as eye color in humans or yellow pigment in Quakers.  In humans, part of one chromosome may look like this.

Each chromosome contains literally millions of genes which code for everything from simple traits such as eye color in humans to personality, size and fertility in Quakers.  The important issue to keep in mind, though, is that each gene has two copies; one on each chromosome in the pair.  If these two copies both contain the same trait (such as light colored eyes in a human or the lack of yellow pigment in a Quaker) then there is no problem and the trait is expressed (meaning seen externally) as a light-eyed human or a Blue Quaker. (since it lacks yellow pigment)

Dominant and Recessive Traits:

True genetics come into play when the two copies of the gene have different information such as one coding for light colored eyes and one coding for brown eyes. (whether the light eyes end up being green, blue or hazel is a bit more complicated)  In cases like this, one needs to know which (if either) of the genes "wins" the conflict.  We term the "winner" the dominant gene and the "loser" the recessive gene.  In the above case, brown eyes are dominant and light eyes are recessive in humans.  So, if someone had one copy of each gene, they would have brown eyes expressed. (seen externally)  They would look exactly like someone who had two copies of the brown eyed gene, but would be genetically different.

Genetic Symbols:

When discussing a single and simple trait, such as eye color in humans, it is possible to describe in text what is happening genetically such that it is easily understood by a reader or fellow breeder.  However, when numerous traits and/or sex-linked traits are considered, it becomes confusing in a hurry.  This is why genetic notation (or short hand) was devised.  It is a way to describe complex genetic traits using symbols and makes even the most complicated combination of traits not only easy to follow, but easy to predict as well.

Each mutation occurs at a specific gene. (or site)  A "light-eyed" human is a result of a mutation at the human "light-eyed" gene (AKA "light-eyed" site) while the "Blue" Quaker is the result of a mutation at the Quaker "blue" gene. (AKA "blue" site)  The letter "L" is chosen to describe the pair of genes at the "light-eyed" site in humans and the letter "B" is chosen to describe the pair of genes at the "blue" site in Quakers.  Either a "L" or "l" can be used at the "light-eyed" site in humans and either a "B" or "b" can be used at the blue site in Quakers.  The "L" represents the dominant gene and trait for eye color in humans (in this case brown) and the "l" represents the recessive gene and trait. (in this case light-eyes)  The "B" represents the dominant gene and trait for feather color in Quakers (in this case green) and the "b" represents the recessive gene and trait. (in this case blue)

To review . . .

Any time you see a capital letter or letters, the trait is dominant and any time you see a lower case letter or letters, the trait is recessive.  So, knowing nothing else about the trait, you can predict it's inheritance just by looking at the genetic notation.  All of the mutations on this site are recessive, so whenever you see a symbol capitalized, you know it is the 'wildtype' gene and trait and whenever you see a symbol in small case, you know it is the mutated trait.

(B = wildtype "green", b = blue, P = wildtype "green", p = pallid)

However, there are mutations in other psittacines that display dominant characteristics and it is expected that these will eventually be found in Quakers as well. (an example is a "dark factor" mutation designated by "D" or "d")  Since the mutation is dominant and the capitalization of the symbol means it's dominant, "D" represents the mutation and "d" represents the 'wildtype'.  As this would mess our tidy "all symbols with caps are the mutated genes" rule, a clarification is needed.  This clarification is adding a superscript "+" to any symbol that represents a 'wildtype' characteristic.

To review further . . .

Another way to think of this is to assume a trait we'll call "test" using the "T" as the designated letter for it's gene.  Without knowing anything about the trait, you can predict quite a bit just by seeing what notation is used in the following examples:

So, by viewing genetic symbols, several conclusions can be drawn.  All capitalized symbols are dominant genes/traits, all small case symbols are recessive genes/traits, all symbols followed with a superscript "+" are 'wildtype' genes/traits, and all symbols without a superscript "+" are mutated genes/traits.

Understanding what the symbols mean, we can now place them together in pairs   Here is an example of the possible combinations at the human "light-eyed" site with aviculture lingo in parentheses.

If we take this example to our beloved Quakers, it is no different.  These are the possible combinations at the Quaker "blue" site with aviculture lingo in parentheses.

As you can see from the above two examples, any recessive trait must exist with two copies or it won't be expressed visually.  Conversely, a dominant trait only needs a single copy of a gene to be expressed.  There are several other genetic relationships aside from simple dominant and recessive such as "co-dominance" and "variable penetrance" that are not addressed in the following pages.  These and others are found in other species, but have yet to find their way into Quaker genetics as we're still in the early phases of discovering and categorizing color mutations.

By now you should . . .

       - understand why color occurs in Quakers and the pigments involved.
       - know how the known color mutations are manifested in Quakers.
       - understand what pairs of chromosomes and genes are and what's so important about the fact they come in pairs.
       - know the concepts of dominant and recessive traits.
       - be able to determine the visual color of a Quaker just by seeing the genetic notation and knowing what mutation is being considered. (B⁺B⁺, B⁺b, bb)

  If these concepts are not clear at this point, you may want to review this page again before going on.

Thirsty for more?  Continue the tutorial at the Autosomal Traits page.