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Post by Peter on Oct 24, 2006 17:47:44 GMT 7
I have decided to post a little post trying to give a simple explination about bird colour genetics and their modes of inheritence. Firstly I will give you a little basic run down on how genetics work. Every organism's genetic make up is found in DNA chains which are extremly large molecules found in chromosomes within each cell of the body. DNA is a repeating sequence with a different code. On different parts of the DNA chain and in turn chromosomes are locations of different genes which determine a specific characteristic of the organism (eye colour, height etc). For every chromosome in the cell there is a matching pair. This is because in each pair the organism gets one chromosome from its mum and one from its dad (in sexual reproduction). In humans we have 46 chromosomes (I think), so we get 23 from mum, and 23 from dad (The only cells in the body to have this number of chromosomes are the sperm and egg). On the same location on each chromosome in the same pair is found the same gene type. So for example, the gene that would determine eye colour would be found on the same site in each of the pair (for example the 21st pair). We then have different types of the same gene (these are called allels) for example blue and brown and green eyes in human. Some are dominant over others which are ressesive, ie brown eyes is dominant to blue eyes. So if a person has one gene for blue eyes, and one gene for brown eyes in their pair of chromosomes then the brown eyed gene will mask the blue eyed gene, giving the person the appearance of brown eyes. NOW TO BIRDS! In birds there are several different locations on different pairs of chromosomes that are responsible for different colour mutations (stop and read it again, it makes sence). One group of mutations that are for the same gene location are the blues and greys. Blues is a ressesive gene. so if a bird has one blue gene and one normal green gene in that group it will be green split to blue. Grey however just has to be different to make things more fun! Grey is actually a co-dominant gene with the normal green gene. So if a bird has one green gene, and one grey gene, the bird will be a grey-green. This is because both the grey and green gene are as dominant as each other, and are both displayed. If a bird has a blue gene and a grey gene on the different pairs then the bird will be grey in colour. if it has both grey genes it will be grey. there are other colour mutations that have the exact same mode of inheritence, such as pied (ie for a bird to be pied in needs 2 pied genes in the same pair). Sex linked genes are special. This is because these genes are located on the pair of chromosomes that control sex. In humans males have the XY pair and females have the XX pair, but in birds females have the XY pair and males have the XX pair. This pair have a chromosome that instead of being shaped like a 'X" is shaped like "Y". So if you think about it, the Y is actually an X missing a leg! So instead of having to have 2 pairs of the same gene to determine the mutation, you only need one gene in those who have the Y chromosome. So whichever gene you get on the X chromosome is the mutation that will be exhibited. However in male birds, without the Y, they still need the pair of genes to determine the colour. This is why sex linked mutations are shown more often in female birds that in male birds. These muations in clued lutino, cinnamon, platinum, lime and opaline etc. Not all of these are for the same gene type, ie opaline and lutino are found on different locations on the leg of the x chromosome, so they dont affect each other. You can then mix colour mutations. Because the blue gene and the lutino gene actually do different things to the bird to make it a different colour, you can mix them, and make an albino! so an albino is actually a blue lutino. Same as a blue pied etc. or a cinnamon blue opaline pied! Some mutations are mis-named. White face in weeros is actually the blue mutation, as pearl in weeros is actually opaline. hope this helps! it is full on, but try to give it a go
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Post by Mark on Oct 24, 2006 19:18:34 GMT 7
Peter if i wonted to Produce Creamino Ringnecks wot Parents do i need ?
I have looked for these birds for a while and can not find any at all
(I should NOT have sold the pair i had is sydney befor i moved to QLD )
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Post by Silvercloud on Oct 24, 2006 19:54:59 GMT 7
That explains it pretty well, I think. Thanks for that.
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Post by Peter on Oct 25, 2006 5:56:07 GMT 7
I could go on forever with the explination! and I dont really know that much! lol
I am pretty sure creamino is one of those mutations that is actually two mutations in one. I have a feeling it is cinnamon and lutino mixed together, but let me consult my book!
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Post by Jen on Oct 25, 2006 11:19:46 GMT 7
My book at home on ringnecks has a full explanation on how to breed creaminos so if you can't find it Peter I will post it later tonight when i get home.
Also Peter I LOVED your explanation, it is actually starting to make sense to me now so I am going to print it and read it a dozen times until it sinks in properly...Thanks heaps
Jen
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Post by Mark on Oct 25, 2006 17:03:03 GMT 7
Im getting a pair soon
Lutino cock Blue Cinnamon hen
wot will this produce?
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Post by Jen on Oct 25, 2006 20:05:43 GMT 7
Ok to breed a creamino here are the possible combinations.... Note you need the pastelblue and lutino mutations to breed a creamino. Flight and tail feathers are white and bird has red eyes and pale coloured feet. Albino x Pastelblue = 25% chance of each of the following... Cocks: Blue/Albino 25% or Pastelblue/ino 25% Hens: Albino 25% or Creamino 25% Pastelblue/ino x Albino = 12.5 % chance of each of the following... COCKS: Blue/Albino , Pastelblue/ino , Albino, Creamino HENS:Blue, Pastelblue, Albino or Creamino Creamino x Blue = 25% chance of the following COCKS: Blue/Albino , Pastelblue/ino HENS: Albino , Creamino Pastelblue/ino x CreaminoCOCKS: 6.25% Blue/Albino ,12.5% Pastelblue/ino, 6.25% Albino, 12.5% Creamino, 6.25% Pastelblue/ino*, 6.25% Creamino * HENS: 6.25% Blue, 12.5% Pastelblue, 6.25% Albino, 12.5% Creamino, 6.25% Pastelblue* , 6.25% Creamino. Pastelblue/ino x Blue 12.5% chance of each of the following... COCKS: Blue/Albino, Pastelblue/ino, Blue, Pastelblue. HENS: Blue, Pastelblue, Albino, Creamino. So as you can see there are no sure ways to breed this bird and it may take quite a few trys to get the desired result. These results are taken from an Australian book called "The Indian ringneck Breeders handbook" by Phil Robson. Eagle, i am sure someone else will be able to more confidently answer your question than me but this may help a little The cinnamon colour works exactly the same as the lutino gene which is sex-linked. so it would be a similar result as you would get from a Lutino x Blue/Lutino I would presume. Blue is recessive and both sexes can be split to blue. I would appreciate Peter answering this one further as he has his head around this genetics things a lot better than I, although I will be studying his post in the hope that I can get a better grasp on it!
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Post by sharkim007 on Oct 25, 2006 22:49:21 GMT 7
THANK YOU!!!!...I UNDERSTAND ALL THIS!!!! Ok so what determines if a gene is dominant or recessive???....... I understand where you say brown is dominate over blue eyes.....so is this like a rule of thumb? .....so to speak.....on what is dominate and recessive......who or what decides if a gene is dominate or recessive???..an example is..both Martin and I are blonde....I am more olive skinned than Martin....now Louisa is fair skinned and a red head....so because I know red hair is recessive.....when she was conceived....her segment...for her hair colour was obviously on my chrosome that is not missing.(because I carry the gene)..so her gene for hair colour was the same for both Martin and I and that is why she is a red head???,,...now my sons......Mitch and Aaron are blonde/brown....Aaron is more olive skined than Mitchell.....so using Aaron as a example...because we know I have Jamician in me...when the conception took place to determine skin tones....my gene....for skin tone was dominate over MArtins....because it appeared on the same places on each gene......so therefore at each conception....each union of egg and sperm...the genetic structure is different.....but depending on which egg meets with which sperm....(because each genetic structure is different???)...will therefore throw the dominate over the reccesive...and produce the offspring..this therefore is why we statisctally state the probability of 25% of this and 25% of that..etc..... So also just to clarify my understanding.....so each chromosone has like segments....so if there is 100 segmetns...and segment number 48 is the size of your feet for example.....if it is a XY....the male dominating gene....because the Y is missing the feet option...the male will dominate..and big feet the result??.....this is presuming that segment relating to the size of your feet is on the peice of Y chromosone that is missing? ??...this is all a hypothetical example... OMG..just reading this..I know what I mean but finding it hard to put it into words..what i mean...lmao...... So......where we have a "throw back"....this is where....the gene might be recessive...(not displayed often).....and at conception.....that characteristic broke through cause each genetic structure is different??...but in the same location on both XX/XY chromosone..and it just so happened on that night..that egg met that sperm and out turned a surprise like with your baby wieors that are OMG colour???....so meaning receessive in both XY/XX.... So how will I know what segment = what characteristic? ?.... Peter if you loose me on this...I'll draw on paper what I mean.....on Sunday....
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Post by sharkim007 on Oct 25, 2006 22:54:47 GMT 7
LMAO...I just read my own post..and if anyone can follow that...your lucky.......
BWahahahaha...might be a lot easier if I draw it Peter.....I can see in my head what I mean..but words have escaped me.....
Ahahah..you can tell when I am being analytical...I say therefore alot!!!! and repeat myself......
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Post by sharkim007 on Oct 25, 2006 23:13:55 GMT 7
Ive got an easier way to explain it.......aahahha using blood groups as an example...... I am O+ Martin is AB- Louisa and Mitch is B+ Aaron is a A+... .O must be recessive...and A and AB dominate...I carry the + gene....the blood determination is on both Martins and my chromosome...not one of the missing bits on the chromosone unless the + or - is....located elsewhere.... So when we conceived the kids..they would be +..because I dominate and carry the gene......but A and AB is dominate on MArtins...over my O recessive.....cause we produced....A and B kids... UNLESS......and this is where the % comes in...at their conception........I have a little hidden -....that then could produce a child with a AB or A-...so a throw back occurs or a "surprise"....that is why - is recessive..... Is that clearer....... ?.. Therefore that is why it is good to know the line heritage to establish more accurate offspring productions???....
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Post by sharkim007 on Oct 25, 2006 23:52:08 GMT 7
Now to even expand further again..using the blood groups and Louisa is a example.....
She now carries the dominate A/ B and +, and recessive O and minus.....
IF she mates with a male who is O-..
their offspring "could" be....a combination of all blood groups but with a higher probablility of A's and AB's positive.....
Unless the recessive breaks at conception.....as she carried all rhesus factors....through with both of them having a - blood group.
Now if she mated with a A+
Depending on his linage.....
Totally higher probability of all A's and AB's +'s....
So really she could throw anything.....depending on her mate....and whcih genetic egg meets which sperm....
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Post by Amanda on Oct 26, 2006 4:48:09 GMT 7
O......M.......G.......! I loved Genetics in HIgh school but you have just confused the C*** out of me!!! LMAO
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Post by Peter on Oct 26, 2006 7:13:20 GMT 7
Thanks jen So creamino is actually a pastle lutino. Just like a silver and a sky blue are actually cinnamon grey and cinnamon blue. lol Renee! I am not 100% on blood types, I have never actually studdied them, so I don't know which ones are dominant and how the + and - work. But from What you have said you explination sounds spot on. I actually did understand the first post. It is important to remember that there isn't just one factor that controls things like hair colour and height etc. Although you do have one major factor, there are others. With you and your kids, I'd say that both you and martin have both the blood and red coloured hair genes. This is not to say there are other genes that control the shade of the hair, or darkness or somthing like that. The jamician skin colour is a funny one! Did you see those twin girls in the paper, one was very dark, the other very fair? that was from the jamician genes. It is extremly hard to try and explain genetics. I find it is always best to explain it with something simple. BACK TO EYE COLOUR!!! You wanted to know about a throw back. A throw back is a gene that would exist in individuals as ressesive and not be shown. so from generation to generation the ressive gene is passed on (with the individuals having say one blue eyed gene and one brown eyed gene giving brown eyes), until finially an individual is produced with both ressesive genes giving blue eyes, and the term throw back is given! The gene has been alive in the population or family all this time, but just never had the chance to be shown. Now you wanted to know how DNA and chromosomes worked.......... Well for that I am going to have to use a board! lol. But all you need to know is that for our cells to function properly we need protiens. There are thousand of different proteins, and the dna chain is what is responsible for producing these proteins. Each protein does or leads to a different function in each cell and in turn apperrance of each cell. leading to how the individual looks. To determin what offspring you might get from a pairing of individuals a method called punnet squares is used to determin the offspring. Basically, you make squares with the mothers pair of genes of one side, and the fathers along the top. You then match the pairs (one from dad one from mum) together to get all the possible outcomes. Here I have made one up for a pair of birds. It is known that both birds are green split to blue. We represent the dominant green gene as a big "B" and the ressesive blue gene as a little "b". I have made the colour of mums genes pink, and dads blue so you can see where they come from. BB would be a green bird not split to anything, Bb would be a green bird split to blue and bb would be a blue bird. so you can see that there is 1/4 or 25% chance of getting a normal green, 1/2 or 50% chance of getting a green bird that is split to blue and 1/4 or 25% of getting a blue This can then be extended to do more than one colour. this is where it becomes confusing. in this example I will do a pair of birds that are both green split blue split pied. "B" and "b" will be used for blue again while we will use "P" and "p" for normal and ressesive pied respectivly. so mum and dad would both be represented as BbPp. We then find every possible outcome for each parrents sex cells. Ie BP, Bp, bP, bp we then fill out the following punnet square (i stuffed up when doing this, i think i corrected it again) Hope this helps a bit more it is full on and extremly hard to explain, especially over the net! here r some videos that may help too. Not the best but worth a look youtube.com/watch?v=SosD_bWWI7M www.youtube.com/watch?v=edC2zotxV54
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Post by Peter on Oct 26, 2006 7:16:29 GMT 7
Also renee, Not all genes are found on that leg of the sex chromosome pair. very few are. You have to remember in humans we still have 23 pairs of chromosomes that are all XX that still contain genetic info. genes are also found on the sex chromosomes but on a location that is not where the leg is, so the mode of inheritance is not sex linked. The majority of genes are inherited normally as domminanted or ressesive genes in a pair.
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Post by Mark on Oct 26, 2006 17:31:15 GMT 7
English Please !! lol
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