About how we came to this life, or
Gene of blue eyes in cattery Ermine Trace
Nothing foreshadowed when one day pair Schoenweg Teodoro (BRI ns 11 33) and Ermine Trace Olwen gave birth me a silver shaded cat Ermine Trace Nadeya. The pair did mating not for the first time, these parents already had kittens - a cat ns 11 with good green eyes and a boy ny 11 33 with "so-so blue", so no miracles were expected. However, the born cat turned out to be strange. Although in general her color corresponded to the usual color, not the lightest ns 11 "made" on the spot, she had blue eyes that shone red in color. Also at birth she had a pair of features that indicated the presence of a small amount of white in color: a pink finger on the hind paw and an asymmetrical outline of the nose - half of the stroke on the left is exist, and the other half, on the right, is practically absent.
The cat was very bright, spectacular and not bad by type. DNA-test confirmed that she really ns 11 - the carrier of the color gene, but not the color-point (genotype Ccs). I was interested in the inheritance of her blue eyes and the ability to reduce to zero the white in color. It always seemed to me that the blue-eyed ns 11 would look better than the green eyes, and would be more interesting than the ordinary ns 11 cats. Nadeya remained in the cattery.
The inheritance of any attribute may be not monogenic, even if we very want it. But the first assumptions, especially in the absence of statistics, are, of course, always the simplest. So we immediately faced simple questions: is this trait inherited? If so, how is it inherited - monogenic or not? If monogenously, then what kind of gene is responsible for the appearance of the trait - dominant or recessive?
Mother Nadeya, Olwen, is an ordinary green-eyed ns 11. Father, Teodoro, is a rather dark silver shaded color-point ns 11 33. Both have full test from the laboratory Orivet in Australia. They are really ns 11 (with the genotype Ccs) and ns 11 33 (with the genotype cscs). Neither one nor the other has any signs of white in color: black pads of the paws, symmetrical strokes, without any doubt expressed shade on the noses. Of course, it's hard to say something definite about the medallions in the groin or on the chest, that both parents - shaded silver, although not the lightest. But anyway, there was no reason to suppose that they had a non-specific white patch, whether explicit or hidden, before the birth of Nadeya.Consider the pedigree of Nadeya. For those of her ancestors who were the producers of the cattery, links to photo albums were added and information on the number of kittens born in our cattery Ermine Trace. About some producers is know that they gave other kittens of ordinary colors, but in other catteries. So Eric von Bürgersruh long and fruitfully participated in the Pearl of Empire's cattery program, I saw many of his descendants personally, so I can safely say that he gove substantially more ordinary kittens, than 38 born in Ermine Trace.
| Ermine Trace Nadeya (BRI ns 11 61), 12.10.2016 | |||
|---|---|---|---|
| PARENTS | GRANDPARENTS | GREAT-GRANDPARENTS | GREAT-GREAT-GRANDPARENTS |
| Schönweg Teodoro (BRI ns 11 33) 38 ordinary kittens + 1 exclusive | Schönweg Xavier (BRI ns 11) | Schönweg Liebeszauber (BRI ns 11) | Kashmir Dewberry (BRI ns 11) |
| Schönweg Astrid Weiβewolke (BRI ns 11) | |||
| Schönweg Ornella Muti (BRI ns 12) | Schönweg Giannino Weiβ (BRI ns 11) | ||
| Kitty von Bürgersruh (BRI ns 12) | |||
| Schönweg Mona Lisa (BRI ns 12 33) | Schönweg Dorian (BRI ns 11) | Kashmir Dewberry (BRI ns 11) | |
| Passimilla's Upper Class (BRI var ns 11 33) | |||
| Passimilla's Upper Class (BRI var ns 11 33) | Ali G. v. den Lauselümmeln (SRS ns 11 33) | ||
| Passimilla's Querima (BRI bs 21 33) | |||
| Ermine Trace Olwen (BRI ns 11) 4 ordinary kittens + 1 exclusive | Ermine Trace Winnie-the-Pooh (BRI ns 11) 8 ordinary kittens | Schönweg Ocean in Love (BRI ns 11) >4 ordinary kittens | Schönweg Giannino Weiβ (BRI ns 11) |
| Kitty von Bürgersruh (BRI ns 12) | |||
| Ermine Trace Laura (BRI ns 11) 7 ordinary kittens | Eric von Bürgersruh (BRI ns 12) >38 ordinary kittens | ||
| Schönweg Camila Blanchefleur (BRI ns 11) 16 ordinary kittens | |||
| Ermine Trace Daura (BRI ns 11) 3 ordinary kittens | Golden-Rochfort vom Goldenen Winkel (BRI ny 11) >5 ordinary kittens | D*Golden Toby v. Wahrberg (BRI ny 11) | |
| D* Lady Ondra v. Goldenen Winkel (BRI ny 11) | |||
| Ermine Trace Trina (BRI ns 11) 7 ordinary kittens | Ermine Trace Kamelton (BRI ns 11 33) 12 ordinary kittens | ||
| Ermine Trace Laura (BRI ns 11) 7 ordinary kittens | |||
My reasoning was as follows. Suppose that the gene responsible for the appearance of the trait is inherited and received by Nadeya from her parents (one or both). The first "suspect" for possible concealed carriage - of course, the father, Schoenweg Teodoro. He is a color-point, and it is not known what color his eyes would be if not for the work of a pair of alleles cscs. In addition, the cat was imported and is the result of alien breeding, for which one can never be believed. Fortunately, with Teodoro we have a long, fruitful work. He gave us 39 kittens from different cats, and only one kitten out of 39 turned out to be "strange."
Normally, Teodoro was mated with cats - carriers of color-point gene, so quite a significant part of his kittens (13) turned out to be color-points. All these color-points - ordinary color-points with a thermo-dependent color, black pads, symmetrical strokes. By the way, Teodoro's eye color was marvelous, but none of the 13 color-point kittens inherited it. In the brightness and depth of the color of the eyes, all children were inferior to their father. However, about the "true" color of the eyes of the kittens, same as the about "true" color of Teodoro's eyes, we can not say anything definite. But the remaining 25 kittens were definitely green-eyed. Not blue-eyed, not odd-eyed, not any more. No evidence of the presence of white in color of either of them also existed.
Theoretically, one of these kittens could be the so-called "latent", which are found among the cats with Altai gene (even the non-blue eyes of latents can glow red, and in the offspring they regularly give kittens with blue eyes). However, those Teodoro children, who were sold in breeding or participated in the breeding program of our cattery, neither blue-eyed nor odd-eyed kittens were given. And there were no kittens among them with any amount of white. In any case, I do not know anything about the birth of such kittens.In the light of all of the above, the version of "Teodoro is the carrier of the dominant type of the Altaian gene or Ojos Azules" implies a situation similar to the one in which a cat scottish fold from a mating with different straits would give 38 straights and one fold. Of course, anything can happen in the world. But the probability of such a strange event is not too great.
Now let's look at the second candidate for carriage / possession of the blue-eyed gene - the mother of Nadeya, Ermine Trace Olwen. Pretty fortunate that this is the cat of my breeding, that is, I know exactly from whom she was born and who else her parents born. However, the progeny of the Olwen, alas, is not numerous and not indicative. In addition to Nadeya, Olwen gave birth 4 more kittens from two different males. Two of them - color-points (golden-point boy and silver-point girl), two - the usual green-eyed silver shaded. All have no white spots, no blue-eying or odd-eying. But five kittens are five kittens, conclusions on such sample to do is not necessary. Suppose Olwen was a green-eyed carrier of the new gene, inherited from at least one of the parents. From whom did she theoretically inherit it?
Pedigree Olwen is remarkable for the fact that the first and only color-point male in it is only in the fourth generation, and he is my, was born as a result of hard inbreeding of two green-eyed silver shaded cats (daughter ns 11 was mated with her father ns 12). All other ancestors are green-eyed. So if our Olwen - the owner of the dominant gene in a latent state, then this gene should be not simple latent, but permanently latent. This hypothetical dominant (or even two dominants) had to successfully hide their existence from the breeders already for nine generations (in the ninth generation in the Nadeya bloodline for the first time appear color-point cat, whose blue eyes could serve as a kind of "mask" behind which the breeders would not notice the new specific trait). If, of course, someone did not hide something.
But if someone has hidden something, it is not with respect to Nadeya's grandfathers on the mother line, i.e. parents Olwen. They are both is of my breeding. In their born was involved the same green-eyed cat ns 11 – Ermine Trace Laura; Olwen is the result of inbreeding on Laura. And Laura is the daughter of two ancestors of the cattery – Eric von Bürgersruh и Schoenweg Camila Blanchefleur.
Camila was not carrier of color-point gene (confirmed by DNA-test) and give birth only green-eyed kittens. From different males (including, by the way, and father Olwen), she gave birth a total of 16 kittens. All green-eyed. All without white.
Eric was a color-point gene carrier, but he was mated mostly with cats without a color-point gene. In our cattery from him was birth 38 kittens (of which only 8 - color-point, and the remaining 30 - ordinary ns 11). In addition, he gave many more kittens from the cats of the cattery Pearl of Empire, in which he spent the first year after his arrival from Germany. Among all this set of kittens was not a single blue-eyed non-color-point, not one of the odd-eyed kitten, not one kitten with signs of white spotting.
So, the daughter of these two producers, Laura, was left in the cattery and was mated with the male Schoenweg Ocean in Love (BRI ns 11) (by the way, a pretty close relative of her mother). From this mating were born 4 kittens of color ns 11. Ocean in Love, according to my information, was not the carrier of the color-point gene and gave only non-color-point kittens (naturally, green-eyed, like himself). In any case, I do not know about any odd- or blue-eyed descendants of the Ocean. One of these four kittens, Ermine Trace Winnie-the-Pooh, remained in the cattery and became the father of Olwen and Grandfather Nadeya.
In total, 8 kittens were received from Winnie the Pooh, of which - 2 color-point kittens (both without color defects, sold in breeding, and no reports of non-standard offspring were received from their owners). The rest of the kittens were ordinary green-eyed, also without signs of white. One of these kittens was Olwen.
Also from Laura on inbreeding (she was mated with her inbred half-siblings Ermine Trace Kamelton) was born a green-eyed cat Ermine Trace Trina, ns 11. She was mated with the green-eyed golden male Golden-Rochfort vom Goldenen Winkel, who for a long time was the main producer of the cattery My-Mirage. Rochfort hade mating with different cats, but I never gave blue-eyed, odd-eyed kittens and kittens with white, as far as I know. We personally, having mated with Rochfort our cats Trina and Abbatisse, received from him in the sum 5 kittens: all ns 11, all green-eyed, all without white. Trina subsequently was mated again with a male ns 11, not carrying a color-point gene; In total 7 non-color-pointed kittens were received from her. Again, all ns 11, all green-eyed, all without white.
Green-eyed daughter of Trina and Rochfort – Ermine Trace Daura – was left in the cattery and was mated one and only time, with Winnie-the-Pooh. She gave born three green-eyed cats (ns 11), one of which was Olwen, mother of Nadeya.
Thus, the assumption that Olwen was the carrier of a dominant in some latent state implies that in the same state, this dominant was present in all its ancestors in 9 generations, as well as at least half of all the offspring they had given born, - the half that was supposed to be lucky to inherit from this latent predecessor this hypothetical dominant. That is, this dominant gene in its latent state is "encrypted" even better than the recessive color-point gene: the latter still found its presence due to hard inbreeding, and the first did not declassify even this.
What is not too surprising for a recessive gene is very strange for a dominant, even with partial penetrance and variable expressiveness. So partial and variable, that in dozens of kittens with enviable constance go to zero, not leaving us to memory neither a blue eye, nor a pink finger, nor an asymmetric white spot on the nose.
We can assume that the white spots were still there, but only on silver and golden cats they were not at all visible: latents with white medallions in the groin and on the chest remained unidentified. Therefore, we knew nothing about them until the cunning dominant risked increasing its expression so much as to whiten a part of the finger and nose and make the blue eyes (as for Nadeya). In other words, for more than ten years we actively mated latents and did not even suspect they were latents. Now, apparently, we can mate them as much and with the same success...
But it was not there.
Nadeya's kittens have not yet reached adulthood, so the analyzing cross Nadey х her son had to move into an uncertain future. To begin, I decided to test the assumption of a recessive inheritance, mated Nadeya with the available half sibling, Ermine Trace Kashemir, Nadeya's brother by the father. If Teodoro was the carrier of at least one recessive gene of blue-eyes, then he should have transferred it to half of his kittens, including his son Kashemir (ordinary green-eyed, without white). And if Teodoro is not a carrier, but the owner of a recessive gene of non-colorpoint blue-eyes, then he had to guarantee that this recessive gene could be transmitted to all his children in general.
The first mating gave nothing. Two green-eyed kittens were born with no signs of white, one golden and the other silver. I lighted their eyes them very carefully. No miracles, no non-standard reflections. Ordinary green eyes. Pretty good. The cat from this mating (Ermine Trace Xtravaganza) remained under supervision in the cattery. Just in case.
But the re-mating brought us four silver kittens: one color and three ordinary patches ns 11. One fine day I found a pink finger on the back foot of one of the small kittens, boy Ermine Trace Ember, (just like Nadeya, only the other leg and the other finger), and then the red glow of the eyes, the left one always glowing, and the right one occasionally (the glow could be detected in about one photo out of ten). The kitten’s nose is ordinary, symmetrical. Also, there was a red glow on the right eye of one of his sisters, Ermine Trace Enya: This cat has no signs of white at all.
After waiting some time, I became convinced that the right and left eyes had a different color in both kittens: one eye promises to be blue, like color-points (of the cat er's has the left, of the cat's right), and the other green, like the of usual silver shaded cats, with the difference that of the male he sometimes gives a red reflection, and of the cat - no.
Thus, an unequivocal answer was received to the very first question: is the trait inherited? Obviously, yes, inherited. Wherein, the degree of its manifestation varies. For clarity, I made a scheme of inheritance, complementing Nadeya's family tree with the results of her last two matings with Kashemir.
As soon as the blue-eyed cat gave birth to odd-eyed kittens with less white or no white at all, there is variable expressiveness, as in the Altai gene. In the case of the Altai gene and Ojos Azules, the amount of white significantly increases when mating blue-eyed (odd-eyed) cats to each other, and homozygotes, presumably, besides this, there is also deaf (Altai) or have even a violation of the skull structure (Ojos Azules). Therefore, blue-eyed and odd-eyed can not be bred "in itself." In our case, on inbreeding, the amount of white has not increased, even slightly decreased, however, we cannot be sure that two carriers of the recessive were mated, and not the owner of the dominant gene with a cat that does not have this gene. For check is necessary mating blue-eyed with blue-eyed, as well as with unrelated green-eyed cats.
I will add that, as can be seen from the diagram, both lines (of father and of mother) in the pedigree of Nadeya are combined at the top, that is, the parents have common roots and are quite close to the Bürgersruh cattery. Graduates of Bürgersruh participate in breeding of catteries Schoenweg and our Ermine Trace. And therefore, it is all the more strange that all this time, despite repeated inbreeding, the blue- and odd-eyes gene did not make itself felt. Especially if it was a dominant gene like Altai or Ojoz Azules, homozygosity for which is fraught with serious defects in color (colors with white are not allowed in chinchillas), as well as deafness and, possibly, other, even more serious defects.
By the way, Nadeya’s pink finger was partially stained with age, and this means that in our case very small white spots may become completely imperceptible..
Conclusions
Despite the fact that the available data do not contradict the assumption of recessive inheritance and suggest that the dominant is extremely unlikely, it is possible that Nadeya’s blue-eyed eyes are the result of a spontaneous mutation that arose "de novo" and not was inherited. In this case, the inheritance of the mutant gene may also be dominant. Thus, we still have two options:
1) Nadeya and two her odd-eyed kittens are homozygous for the recessive blue-eyed gene. The gene has variable expressiveness, but, as far as can be judged by the three kittens obtained, it implies only a very small amount of white. All the green-eyed kittens of Nadei (3), her color-point kitten, the father of kittens Kashemir, the father and mother of Nadeya are at least the carriers of this recessive gene. Given the variable expression, some of them can be homozygotes that are apparently not distinguishable from the usual green-eyed ns 11 and color-point ns 11 33.
2) Nadeya and two her odd-eyed kittens - heterozygotes for the dominant, newly emerged gene of the blue-eyed. The gene also has variable expressiveness and also has so far meant only a very small amount of white, although in this case the sample is categorically insufficient for conclusions. At least part of the green-eyed kittens Nadei did not inherit the blue-eyed gene, but among these kittens there may be latents - kittens that have the gene, but its expression is minimal.
In this connection it is necessary first of all:
1) To make several matings of blue-eyed and odd-eyed cats with unrelated green-eyed cats who have never given non-colored blue-eyed kittens and kittens with white. If we are dealing with a newly emerged dominant, the appearance of blue-eyed kittens from such matings will be sad evidence that this is the case.
2) To make several matings of blue-eyed and odd-eyed cats each other. In the case of mating of two owners of a recessive gene, there should no kittens other than blue-eyed, odd-eyed or latent, in the litter. If two carriers of the dominant gene are mated, 25% of kittens will be completely free of it, and 25% will probably find undesirable signs characteristic of homozygotes for Ojos Azules and the Altai gene.
Will be working.
UPD:
In order to find out whether our hypothetical gene of blue-eyes is the gene of piebald spotting Ws, all three (Nadeya and two of her odd-eyed kittens) were made DNA-tests in the UC Davis laboratory. The results confirmed that none of the three animals is a carrier of Ws. Links to DNA-test: Nadeya, Enya и Ember.
UPPD:
From Nadea's mating with an unrelated cat Lusy-Mur Dionis was born the kitten Ermine Trace Lazurit (chinchilla-point with one pink finger on each hind paw). Thus, the dominant, not recessive, inheritance of the gene of blue/odd-eyes can be considered proven.