So, what is it that makes Seraphim so special genetically, this “thing” that causes them to transform from a red Satinette color pattern to a pigment free, pure dazzling white? And how does this differ from the white of other pigeons in pattern of inheritance? And what else is going on genetically in Seraphim that makes these Fancy Pigeons different than their breed of origin, the Classic Oriental Frill?
Let’s start with some basic definitions and descriptions of what we know at this point, based upon breeding experiments, of the crucial genetic components that make Seraphim special beings. First is the “Seraph Color Gene Complex“— the combination of genes that cause recessive red to appear as well as the transformation of that red to white. Second is the Satinette piebald pattern of color distribution. The three genes of the Seraph Color Gene Complex – overlaid on the Satinette piebald color pattern – are “recessive red” combined with the “white-sides gene” and an as yet undefined “tail-whitening” gene. (I have a theory that the so-called white-sides and tail whitening “genes” may not be genes at all. Rather, they may simply be genetic “switches” that shut down pigment production. As genetic switches they are inherited, but they are not “genes” per se. Genes direct the manufacture of specific proteins. Switches are gene controllers, i.e. DNA segments that turn – in this case – the recessive red gene to “on” to produce pigment briefly in the juvenile, and then “off” again to create the absence of pigment in the adult, resulting in pure white.) The Piebald genetics that make the “Satinette” pattern of a pure white body with colored wing shields and tail has been long established and, along with the Seraph Color Gene Complex, is presumed to be integral for Seraphim to turn completely white. The inheritance of Satinette piebald genes and their patterns of visible expression are poorly understood and may also be a consequence of switches as well as actual genes. Whatever the DNA analysis eventually proves about how white is made manifest in Seraphim, we know that Seraphim contain the Satinette piebald color pattern overlaid with the Seraph Color Gene Complex, and it’s the “white-sides” gene and “tail whitening” gene (or genetic switches) that ultimately turns off the Recessive Red or Yellow Satinette color pattern and creates the pure white Seraph.
Let’s further define the component parts of the Seraph Color Gene Complex:
RECESSIVE RED MUTATION: The recessive red mutation is a recessive gene on one of the regular (autosomal) chromosomes which, when transmitted from each parent, overrides or masks the primary ash red, blue, and brown sex-linked genes that normally determine the basic color of all pigeons. It usually masks patterns as well—with exceptions. Birds with a pair of these recessive genes will appear “red”, while birds with only one of these genes will show the color carried by their sex chromosomes—ash red, blue, or brown. Recessive red is epigenetic to all other colors except recessive white and albino, i.e. it hides or “paints over” them so they are not visually expressed. Recessive red does not “paint over” white piebald areas or stencil patterns.
THE WHITE-SIDES GENE: The “white-sides gene” is a recessive autosomal gene expressed ONLY in recessive red or recessive yellow (dilute red) birds. Pigeons of other colors may carry the gene, but you will never see it expressed. If a recessive red or yellow pigeon carries one copy of the white-sides gene, the wing-shield will turn partially white or “rose” with the first adult molt; if it carries two copies the wingshield will turn completely white. Seraphim are homozygous for “white-sides”; they carry two copies of the gene so it is fully expressed. (Again, I’m not so sure “white-sides” is a gene; it may actually be a switch that turns the pigment production gene on and off, or a mutated master controller that tells the switch to turn off the gene that produces pigment.)
THE TAIL-WHITENING GENE: The “tail-whitening” gene is a separate autosomal gene (or genes) that causes the tail to stop producing pigment and turn white. The mechanism is not understood. (Probably not understood because, until only recently, no one understood the concept of “master controllers” and “switches” in regard to genes. Again, I suspect the “tail whitening gene” is really just a mutation in the master controller that causes it to signal the genetic switch to flip to “off” at a certain point in feather pigment production. This will eventually be proven one way or another.)
How it works (as far as we know…)
For simplicity, and since we don’t yet know for SURE, we’re going to pretend that the Seraph Color Gene Complex is a combination of genes rather than genes and switches and master controllers. So let’s begin that way…
In the Seraph Color Gene Complex, first noticed in the loft of Anya Ellis in 1986, the recessive red, white-sides, AND some unidentified tail-whitening genes were somehow all accidentally inherited together in two offspring of Classic Oriental Frill Satinettes, which already have established piebald gene inheritance which makes the whole bird white except for the wingshields and tail. This Satinette color pattern and piebald gene combination has remained in the Seraphim population ever since, and is the defining background genetic color pattern characteristic. The visual color pattern in juvenile Seraphim is therefore entirely white with the recessive red gene showing up only as red marked wing-shields and tails, as one would expect for a Satinette piebald marked bird. What remains unexplained and unusual about the color transformation from red to white in Seraphim is that the white-sides and tail-whitening genes turn on variably part way through the fledging process, turning off pigment production sometime early in juvenile feather production, resulting in varying amounts of red coloration in the wing shields and tail with an abrupt change to white part way through feather development. The feathers that would normally be pure red in a juvenile because of the recessive red genes are instead merely splashed with red on the tips or part way up the feather shaft due to the stoppage of pigment production. Some youngsters will thus demonstrate more red color in the wing shields and tail, and others will seem to have only been dipped in red on the tips, depending upon when pigmentation stopped. Normally white-sides is not expressed at all until the adult feathers come in, so the way in which this occurs in Seraphim as juveniles is different than usual. The concomitant whitening in the tail in this manner has otherwise not been described occurring in this way either.
When the adult molt occurs a few months later, ALL the adult feathers come in pure white, as once activated, the Seraph Color Gene Complex prohibits the production of pigment for the rest of the bird’s life. The only time color will ever be seen in a Seraph is thus with initial feather development in the nest. As far as we know, no other white Fancy Pigeon in existence owes its absence of color pigment to this combination of genetic processes; thus Seraphim are unique in this way.
This 5-week old Seraph demonstrates the visual effects of the Satinette pied genes, the white-flight gene, and the recessive red gene. Color is primarily expressed on the wing shields and tail in Satinette pattern. Only the tips of the feathers are red due to early termination of pigment production during the formation of the juvenile feathers. (See discussion.)
The same Seraph after his first molt, now white due to the full expression of the white-sides and tail-whitening genes linked to the recessive red in Seraphim. Note that the red mis-marked feathers in what should have been piebald white areas of the chest and head in the juvenile at left are replaced above with white as well.
OTHER REQUIRED TRAITS: The needle-point peak in the Seraph is autosomal recessive. The unusually ruffled frill (or cravat) is the result of two recessive genes which code for the chest frill (kr1 and kr2) that are both present in the Seraph. The feathered toes are called “grouse” and are a recessive trait—-like a kid glove, each toe is individually seen and individually feathered. The short beak (ku) is polygeneic—i.e. is inherited with the involvement of more than one gene. As you can see, Seraphim carry a lot of recessive traits, all of which have to be donated by each parent and present on chromosomes in pairs in order to be seen.
The visual conversion from recessive red Satinette pattern to pure white as a result of the expression of the Seraph Color Gene Complex—-recessive red, the white-sides gene, and the tail-whitening gene(s) (and likely others)—is an absolute defining trait for Seraphim. Any bird that does not show recessive red (or yellow—the dilute of red) in the wing-shields and tail and go through this transformation does NOT carry the Seraph Color Gene Complex and is not—by definition— a Seraph. Selective breeding for over thirty years has created additional enhancements of body form and feather with an overall refinement and lengthening effect, giving the Seraph an unusually beautiful long flowing line, height, posture, and overall stunning regal look that is distinctly different from the breed of origin, the Classic Oriental Frill. The toe feathers are more refined and delicate, the skull has a more defined arc, the swoop and mane are deeper, the frill is larger, and the beak is more downturned. This is easy to see when comparing the Show Standard for Seraphim to the Show Standard of the Classic Oriental Frill. Over the past quarter of a century the differences between the two breeds have become increasingly evident as the gene pools have become more isolated, concentrated, and distant. The Seraph is a breed of its own.
SOME MORE VERY BASIC PIGEON GENETICS FOR THE BEGINNER
(Please note the links in this article to Wikipedia entries and other sources that can be helpful. This can all be very difficult even when stated as simply as possible! Yet some basic understanding of these principles is necessary for the breeder of any Fancy Pigeon. The National Pigeon Association website has in-depth articles on pigeon genetics for those who wish to immerse themselves.)
CHROMOSOMES: The pigeon has forty pairs of chromosomes (or eighty individual chromosomes). Unlike other cells in the body, the sperm and the egg each have just forty individual chromosomes, or half the total, thanks to a process called meiosis which occurs only in testes and ovaries. When fertilization occurs and the sperm penetrates the nucleus of the egg, each sperm chromosome finds it’s match in the egg nucleus and pairs up with it. The fertilized egg now has a complete complement of forty paired chromosomes, or eighty total chromosomes, a normal pigeon cell. That cell immediately begins to divide using a new process called mitosis in which all of the chromosomes are duplicated just before division so that each division results in two cells with the full complement of eighty chromosomes. A great deal is now known about how this initial cell becomes an embryo and then a fully developed chick, but the details are too complex to discuss here. Enormous textbooks are written on the subject, and every day massive dissertations as well! It is wonderfully complex and amazing.
Anyway. During meiosis the various genes on the individual chromosomes remain reasonably consistent, but variation exists in the proteins that make up the DNA in those genes. Every time a new egg or sperm is formed there is the possibility that its chromosomes carry tiny changes in the order, or sequence, of the DNA proteins in the various gene segments. It is this possibility for change that results in genetic variability, or differences that may be seen in the fully formed organism.
“Dominant” genes are segments of DNA that always express themselves over any mutation of the same gene sitting on the opposite paired chromosome. For instance, if a mother donates a gene for blue eyes and a father donates a gene for brown eyes, the child will always have brown eyes; brown always dominates any other eye color. The blue gene is there, but it is not visually expressed; it is “hidden” and will only show up if given a chance to pair up with another blue gene in the next generation. That blue gene may be passed on for several generations before finally getting the chance to appear when matched up with another person also carrying a blue gene. The blue gene is thus “recessed”, or hidden—a “recessive” gene. It may also be called a recessive “trait”, or characteristic. Recessive genes or traits become important only when both parents carry them, as therein lies the only possibility for them to be expressed, or seen.
“Partial Dominant”, or “Dominant With Variable Penetrance” are terms used to describe genes that are always expressed—-but to a variable degree—-when present, depending upon the effect of other genetic conditions present. Feathered legs and feet are an example of this phenomenon. The gene that causes this is dominant to the bare leg gene, but the variability in the penetrance—-or visual expression—-of the gene can result in anything from enormous leg “muffs” to “slipper” feathers to “grouse” feathers to “stubble” and anything in-between, depending upon other genes present that add to, or subtract from, the degree to which feather growth on the feet or legs is allowed.
There is also something called linkage. Sometimes genes are locked together and are passed on as a group that cannot be broken apart by the process of cell division and meiosis. In such instances, these linked genes are always expressed together at the same time, so for all intents and purposes the combination acts as if it is a single gene in the way it is passed on or inherited. Linkage may be partially responsible for some of the color changes seen in Seraphim.
So let’s review. Now you understand that each parent bird passes on half of its set of chromosomes in the egg or sperm so that the new chick has a full set of chromosomes—half of them from each parent. You also understand that some genes on chromosomes overpower, or dominate weaker recessive genes at the same location on the opposite paired chromosome; the paired chromosomes may carry a recessive gene each, a dominant gene each, or a combo of recessive and dominant. As Dominant always wins, the only time you can see hidden recessive traits is when they are on both chromosomes in the pair, so the trait has to come from each parent to appear. Linked gene combinations transfer multiple traits to the offspring all at once, and always together, so for all intents and purposes linked genes are inherited as if they are a single gene or trait. The “Seraph Color Gene Complex” is not one gene, but a combination of genes, most of which are independent, but some of which may be linked genes—we don’t know—but we DO know there are a minimum of three and very likely more, and they all have to be present. And by now you know that color genes are not the only thing that make a Seraph, as all the other genes for form must be embedded as well for that beautiful final creation to appear.
SPECIAL CHROMOSOMES: So, let’s go back to those forty pairs of chromosomes once again. One of those pairs has a very special function: it determines the sex, or gender of the bird. This pair has a special name: sex chromosomes. (I know….big surprise, eh?) The other thirty-nine pairs of chromosomes are called autosomal chromosomes, and they program almost everything else in pigeon development with a few exceptions.
In Pigeons the sex chromosomes are called Z and W. The hen is ZW and the cock is ZZ. So the W sex chromosome is responsible for creating the female sex. The hen thus determines the sex of the chick through the egg, as she always donates a half of her set of chromosomes to an egg. By chance, half her eggs will carry a Z and half will carry a W; the eggs with W will produce hens. The cock can only contribute one of his two Z’s, since that’s all he has. In pigeons, the genes for the primary base color of the feathers—ash red, brown, and blue—are also located on the Z sex chromosome. This knowledge can be a useful tool. Since the hen has only one Z, a breeder KNOWS that she has just one basic color gene on her Z chromosome and can pass only that one color gene to ALL of her male offspring. Her color is also true—her appearance matches her one color gene on her Z sex chromosome; if she is blue she carries only blue, if she is ash red she carries only ash red, if she is brown she carries only brown; nothing is hidden from the eye. Her W does not carry a color gene, so her female offspring MUST have their base color determined by one of the two Z chromosomes from the cock, whichever one he contributes at fertilization. One can thus determine what colors the cock is carrying by the colors that are expressed in his female offspring. This is a general basic fact that can be helpful for all breeders.
I wish it were just that simple, but obviously there are other color-pigment and pattern-altering genes present in pigeons or one wouldn’t see all of the different colors and patterns one sees at Fancy Pigeon Shows. Most of these color and pattern modifiers are located on the autosomal chromosomes and a few on the sex chromosomes. No matter what, though, every pigeon has a base color of ash-red, blue, or brown on the sex chromosomes; those colors can either be fully expressed, modified, or completely masked by color-modifying genes on the autosomal and sex chromosomes. This is true in Seraphim too, of course. As you already know, the autosomal recessive red genes in the juvenile Seraph are expressed as a red that covers the true base color of the bird (ash-red, blue, and brown); the recessive red shows in the wing shields and tail, and even though the red is recessive, it masks and dominates the true base color of the pigeon coded for on the Z sex chromosomes because autosomal recessive red is epistatic to all sex-linked base Z colors – it hides them. The pied and white-flight genes show white in the flights and body from the beginning and remain that way. The tail whitening and white-sides genes turn off the visual recessive red of the tail and wing-shields part way through the initial production of feathers. The genetic job is done. A shimmering pure white bird appears that actually has a hidden Satinette color pattern of recessive red that appeared only briefly, and a base color of ash red, blue, or brown that never appeared at all even though the genes are still there. The Seraph Color Gene Complex wins and eliminates all color. You will never see the hidden genetic base color programmed into the Z sex chromosomes in the life of a Seraph, and you will only briefly see the recessive red—the visual clue that indicates a Seraph in the nest.
It IS possible, however, to determine the basic hidden Z chromosome color of a Seraph hen by crossing it with a brown cock of any type. The male offspring will carry her Z color chromosome, and it will be visible since the offspring will only have one half the recessive Seraph Color Gene Complex genes so they won’t be expressed. A Seraph cock paired to a brown hen likewise will show his hidden Z base color(s) in all the offspring. Not that it matters; it’s just interesting if one wanted to know.
EVEN MORE COMPLICATED MATTERS 🙂
SPLIT BIRDS: On occasion a breeder of Seraphim my feel a need to increase the genetic diversity in their flock with an out-cross. An out-cross is like taking a dip in a different genetic pool; an unrelated or distantly related bird is deliberately crossed into a line of Seraphim. If the out-cross is not a Seraph, (Do NOT do this! I am discussing this for reasons of understanding genetics…) the bird chosen would be a quality Old Frill of the oldest type possible, one with a clean long line. In this way one is certain to maintain many of the other traits in the offspring that the two varieties already share, such as needle-point peak, mane, grouse feet, and frill. The best Seraph in the loft is used for this cross. Since an Old Frill out-cross bird must have Satinette markings, all of the offspring of the Seraph/Satinette out-cross will be Satinette marked colored birds carrying one-half the Seraph Color Gene Complex. These birds are called “Splits” (or “AIM” birds in the Seraph world), as their chromosomes are “split” for the Seraph color genes and they cannot be seen even though they are there. This sort of bird is also called “heterozygous.” (A bird with the same trait on each chromosome is “homozygous,” but it’s easier to remember them as either a Seraph or a Split.) This technique of crossing back to the original primordial gene pool was a necessity thirty years ago for the original development of Seraphim (see “The True Story of Seraphim” on this site). It is not so today.
To the left here is an example of a heterozygous, or “Split” (AIM) bird carrying the recessive Seraph Color Gene Complex. The father is a Seraph, the mother is a “Split” brown lacewing spot-tail Satinette. The Seraph color traits are hidden in this bird because they exist on only one half the chromosomes – it looks like a Satinette. This is a very, very colorful bird and is a startling example of the sorts of colors and patterns that may be hidden on the Z and other chromosomes in your Seraphim; but even though it is a second generation from an outcross to a Satinette Old Oriental Frill, it still overall looks too much like an Old Oriental Frill in structure. If crossed back to a really outstanding Seraph, half of its babies would be colored Splits (AIM birds) just like it, and half would be Seraphim, some of which could be of reasonable quality, beginning to look overall more like Seraphim and less like Old Oriental Frills. With each generation the back-cross of a newer generation Split or Seraph to a Show Quality Seraph will result in both better quality Seraphim and Splits (AIM birds) that aside from being color-marked, may eventually have nearly the same look, form, and feather traits seen in Seraphim. The process takes time – as in nearly a decade – as most offspring in the first few generations will not be useful for back-crosses no matter how “pretty” they are as they will have too many characteristics of the Old Frill. One must be scrupulous in choosing only the best AIM birds for breeding back under these difficult circumstances. Today there are few reasons, other than a complete lack of access to an appropriate mate for a Seraph, to make this sort of outcross – it’s a thirty year genetic back-slide. It’s a technique that could be used to re-create Seraphim if the breed were ever lost.
Now, in 2016 and beyond, if a color marked bird were to be used to improve or expand a flock of Seraphim, there is only one line of birds that should be used. The only modern AIM birds (Splits) in existence in the world that truly have the High Superior structural qualities of Champion Seraphim and that could or should be used to improve a Seraph breeding program are in the possession of Anya Ellis. She has maintained a structurally perfect line of AIM birds for two decades. A color marked bird from any other source should not be introduced into a Seraph breeding program.
**So the Best way to do an out-cross to improve your Seraph breeding program is to get an unrelated (as possible) High Superior Seraph (or a pair) from the loft of another dedicated breeder.
And now, I think, that’s enough. 🙂