What is opal and cherry?
This is a summary of a discussion started at the end of July of 2011 and must be taken as a summary of the state of the art.
Opal is described as an autosomal mutation with a big variation of colour and it isn't sex-linked.
A brief introduction to the problem:
(click the images on the text to see them in a larger size)
during many years there was only opal but the phenotype was divided in two classes: red phase opal and blue phase opal. The difference between the two phenotypes was explained by Dr. Willard F. Hollander (1938) as a result of a hormonal condition caused by abnormal functioning of the thyroid.
At the same time there were among the red phase opal a less often observed Ash-red mimic phenotype described as “extreme” opal (Hollander 1938).
started my review o this gene back in the 2001 time frame, but did not complete my work and subsequently publish the finished paper until June of 2010
This "Ash-red mimic" phenotype was studied by Steve and Rebecca Souza, from Rare Colour Lofts. They concluded that this "Ash-red" mimic was a recessive allele to opal and baptised it with the name “cherry”, symbolized as (och). The work started in 2001 and completed with the publish of the paper on June of 2010. This more stable consistent appearing phenotype, (och), was not previously studied, tested and documented prior to this work.
You can read Steve and Rebecca article clicking on this link: Analysis of the Opal color variant of the domestic pigeon (Columba livia).
Complemented with the following photos of Cherry:
|Cherry bar wing||Side look|
At the time of the discussion there weren't any available photos of cherry among the "beginners", like me, and the correct identification of a cherry pigeon was difficult. The last discussion started when a pigeon, ring nº 8038904/08, born at my loft was identified as appearing cherry by Steve in 10/11/10. This pigeon has also an opal (blue phase) full sister, ring nº 9033082/09. The conclusions of Steve studies are incompatible with this occurrence. Since opal and cherry are recessive alleles of wild type, being opal dominant to Cherry, it is impossible that a couple of blue bars are parents of opal and cherry pigeons:
|Parents||Possible cherry daughter: 8038904/08||Opal daughter: 9033082/09|
This is new to all of you. I did not wrote about this to avoid more "disturbance": the 9033082/09 female and her nest brother:
Later in July 2011, the opal/cherry debate was initiated again but now with more doubts about my "cherry " 8038904/08. As we can see, the female phenotype is only a close approximation to Steve photos of a cherry. In August Gene Hochlan wrote the following about the 8038904/08:
"The pied youngster is also definitely a cherry Blue Bar and is lighter because there are no darkening modifiers and it has white feathers. Many Blue bars that are also pied are a lighter blue than those that are not. This is a normal phenomenon. The first cherry Blue Bar R. Homer cock, that I borrowed in 1979, was also pied and so light colored that I had Dr. Hollander look at his picture to make sure he was actually extreme red phase rec. opal (cherry) and not an Ash Red Bar."
and previously affirmed that the following hen, ring nº 9052781/09:
|Dirty Cherry blue bar|
was according to his experience also a Cherry: " It is a cherry Blue Bar in combination with Dirty. I have two identical cherry Blue Bar Dirty hens in the loft right now." To prove his statement he used a photo of a pigeon that he is sure to be a Dirty Cherry:
|Dirty Cherry Blue Checker|
Gene hypothesis is the following: the ancient red phase opal are in fact dirty cherry pigeons. If we remove the dirty the red phase opal will look a "cherry".
Ronald Huntley come to the discussion and argued that:
"However, if you can separate dirty from an old fashion red phase opal and produce a cherry like Steve’s then that indeed would be interesting to see duplicated. Can you do it? True cherry’s are very hard to come by, while old fashion red phase are much more common than the old fashion blue phase. In fact, I would guess the ratio to be something like 10 to 1 or more. So how is that possible since we know from Steve’s report, that blue phase is dominant to cherry. It (blue phase) certainly doesn’t seem to be very dominant to the old fashion red phase or there would be more blue phase than red."
The discussion "ended" with Gene reply:
"You are being reasonable and I will make it a point to separate Dirty from cherry to prove my point. Steve; perhaps you can take the opposite approach and add Dirty to cherry. Would appreciate your help and cooperation."
I don't know if Gene or Steve, or someone else, will have the time and/or the pigeons to do the tests, but they are necessary. After the debate I concluded that I don't have cherry. My supposed cherry pigeons don't have the typical neck feathers phenotype that we can see in Steve and Gene photos (with or without dirty). Like Ronald I also noted the rarity of blue phase opal at my loft. So, yes we have cherry which is an allele to opal, but the variation in opal is not explained and still remains a mystery. An area needing more studies.
Thank you all for participating in the debate.
More recessive Opal examples at my loft:
Genetic symbol - o
|Parents||Male Opal: 1031788/11||The nest brothers|