Posted December 8, 201014 yr Hey guys, I've not go much experience with Sex linked varieties, so I'm come to the experts ! I've recently bred an Dom Pied Light Green Cock with a Cinnamon Light Green Hen. The three chicks were: - Light Green Cock, Light Green Pied Hen, and a Light Green Opaline Hen. So, I assume this indicates the Pied Cock is split for Opaline. Easy. However, when I go to breed the Son ( the Light Green ) which WILL be split Cinnamon and MAY be split Opaline I have questions. If he is just split cinnamon, fine. Simple. However if he is split for both Cin and Opal how does that work ????? I've read about this Gene cross over which suggest that these two varieties link, so 50% of the daughters will be Cinnamon Opaline, the rest Normals ? (Assuming the Hen is a Normal) Or will I get Normals, Cinnamon, Opaline and Cinnamon-Opaline Daughters ? Your wisdom always appreciated. Stew
December 8, 201014 yr Hey guys, I've not go much experience with Sex linked varieties, so I'm come to the experts ! I've recently bred an Dom Pied Light Green Cock with a Cinnamon Light Green Hen. The three chicks were: - Light Green Cock, Light Green Pied Hen, and a Light Green Opaline Hen. So, I assume this indicates the Pied Cock is split for Opaline. Easy. However, when I go to breed the Son ( the Light Green ) which WILL be split Cinnamon and MAY be split Opaline I have questions. If he is just split cinnamon, fine. Simple. However if he is split for both Cin and Opal how does that work ????? I've read about this Gene cross over which suggest that these two varieties link, so 50% of the daughters will be Cinnamon Opaline, the rest Normals ? (Assuming the Hen is a Normal) Or will I get Normals, Cinnamon, Opaline and Cinnamon-Opaline Daughters ? Your wisdom always appreciated. Stew you will get ......... normal , opaline cinnamon , normal cinnamons,normal opalines and if you put to a cin hen you can get all the same but with a chance of cinnamon cocks also in these mutations (opaline cinnamon,cinnamon ) and if its also opaline a chance two get opaline cocks as well in cinnamon , op cin and opaline ;]
December 9, 201014 yr If he is split cinnamon opaline im pretty sure he will breed as follows: 25% normal hens, 25% cinnamon hens, 25% opaline hens, 25% cinnamon opaline hens. 25% normal cocks, 25% normal / cinnamon cocks, 25% normal / opaline cocks, 25% normal /cinnamon / opaline cocks (provided the hen isnt sex linked of course)
December 9, 201014 yr First things first. The Light Green cock you wish to pair as you know is already split for Cinnamon. Now assuming the father passed on the Opaline gene to him he would now be thus: Light Green/Opaline Cinnamon-II Assuming you are going to pair this cock bird to a normal Light Green hen the results are thus: COCKS 16.901% Light Green / Cinnamon 16.901% Light Green / Opaline 8.099% Light Green 8.099% Light Green / Opaline Cinnamon-I HENS 16.901% Light Green Cinnamon 16.901% Light Green Opaline 8.099% Light Green 8.099% Light Green Opaline Cinnamon Dean and GB your percentages do not take recombination into account.
December 9, 201014 yr First things first. The Light Green cock you wish to pair as you know is already split for Cinnamon. Now assuming the father passed on the Opaline gene to him he would now be thus: Light Green/Opaline Cinnamon-II Assuming you are going to pair this cock bird to a normal Light Green hen the results are thus: COCKS 16.901% Light Green / Cinnamon 16.901% Light Green / Opaline 8.099% Light Green 8.099% Light Green / Opaline Cinnamon-I HENS 16.901% Light Green Cinnamon 16.901% Light Green Opaline 8.099% Light Green 8.099% Light Green Opaline Cinnamon Dean and GB your percentages do not take recombination into account. No they don't. I left it out because its pretty un-common, impossible to identify visually - and its a headache to work out in my head
December 9, 201014 yr Author Thanks guys. I was following the logic up until RIP put the percentages down and used Light Green/ Opaline-Cinnamon II ?? What does this mean ? And Re-combination ? RIP are you saying that given the parents / this scenario, there is a higher likelihood of Cinnamon or Opaline Hens than Normal or Cin-Opaline Hens ? I would have thought they would have been the same chance ?
December 10, 201014 yr Thanks guys. I was following the logic up until RIP put the percentages down and used Light Green/ Opaline-Cinnamon II ?? What does this mean ? And Re-combination ? I've read about this Gene cross over which suggest that these two varieties link, so 50% of the daughters will be Cinnamon Opaline, the rest Normals ? (Assuming the Hen is a Normal)[/Quote] Crossing over is where the genes cross from one chormosome to another, re-combination is the reverse of that process. In order to find out what may happen you need type what type of crossover happened in the first place. Hence the term, Opaline Cinnamon-II. What this means is the cock birds carries the Opaline gene on one chromosome and the Cinnamon gene on the other. They are not linked i.e. on the same choromosome and therefore will not be passed on together at each choromosomal split. There is a small chance however over crossing over or recombination. This is where the two genes can occupy the same choromosome. When the two genes occupy the same chromosome it is thus written as Cinnamon Opaline-I or it can be written as Cinnamon-Opaline (the hyphen between the words denotes linkage, no hyphen no linkage). RIP are you saying that given the parents / this scenario, there is a higher likelihood of Cinnamon or Opaline Hens than Normal or Cin-Opaline Hens ? I would have thought they would have been the same chance ? Yes there is a higher likelihood because the genes carrying the Cinnamon and Opaline will sort independantly of each other. There is a 50/50 chance of getting one or the other but a minimal chance for the genes to cross over onto one chromosome and then be inherited together. The incidence of cross over in Opaline and Cinnamon is quite high, around the 30% mark from memory as they are approx 30 map units apart. Edited December 10, 201014 yr by RIPbudgies
December 10, 201014 yr Thanks guys. I was following the logic up until RIP put the percentages down and used Light Green/ Opaline-Cinnamon II ?? What does this mean ? And Re-combination ? I've read about this Gene cross over which suggest that these two varieties link, so 50% of the daughters will be Cinnamon Opaline, the rest Normals ? (Assuming the Hen is a Normal)[/Quote] Crossing over is where the genes cross from one chormosome to another, re-combination is the reverse of that process. In order to find out what may happen you need type what type of crossover happened in the first place. Hence the term, Opaline Cinnamon-II. What this means is the cock birds carries the Opaline gene on one chromosome and the Cinnamon gene on the other. They are not linked i.e. on the same choromosome and therefore will not be passed on together at each choromosomal split. There is a small chance however over crossing over or recombination. This is where the two genes can occupy the same choromosome. When the two genes occupy the same chromosome it is thus written as Cinnamon Opaline-I or it can be written as Cinnamon-Opaline (the hyphen between the words denotes linkage, no hyphen no linkage). RIP are you saying that given the parents / this scenario, there is a higher likelihood of Cinnamon or Opaline Hens than Normal or Cin-Opaline Hens ? I would have thought they would have been the same chance ? Yes there is a higher likelihood because the genes carrying the Cinnamon and Opaline will sort independantly of each other. There is a 50/50 chance of getting one or the other but a minimal chance for the genes to cross over onto one chromosome and then be inherited together. The incidence of cross over in Opaline and Cinnamon is quite high, around the 30% mark from memory as they are approx 30 map units apart. Hi All, Sorry to be a pedantic so-and-so, but crossing over and recombination are pretty much the same things. Recombination is the result of crossing over as opposed to the return to normality or the status quo. Your definition suggests that the chromosomes re-unite at the same locus (recombine) where the reality is that the chromosomes will cross over or "recombine" at a somewhat random point , albeit the further from the chromosomes centromere, the greater the chance of crossing over I believe. Rip you are on the money with your percentages and I would say that 1 in 12 hens from this mating being cinnamon opaline is a relatively common event when referrring to crossing over events. Hope this helps. Cheers PT
December 10, 201014 yr Thanks guys. I was following the logic up until RIP put the percentages down and used Light Green/ Opaline-Cinnamon II ?? What does this mean ? And Re-combination ? I've read about this Gene cross over which suggest that these two varieties link, so 50% of the daughters will be Cinnamon Opaline, the rest Normals ? (Assuming the Hen is a Normal)[/Quote] Crossing over is where the genes cross from one chormosome to another, re-combination is the reverse of that process. In order to find out what may happen you need type what type of crossover happened in the first place. Hence the term, Opaline Cinnamon-II. What this means is the cock birds carries the Opaline gene on one chromosome and the Cinnamon gene on the other. They are not linked i.e. on the same choromosome and therefore will not be passed on together at each choromosomal split. There is a small chance however over crossing over or recombination. This is where the two genes can occupy the same choromosome. When the two genes occupy the same chromosome it is thus written as Cinnamon Opaline-I or it can be written as Cinnamon-Opaline (the hyphen between the words denotes linkage, no hyphen no linkage). RIP are you saying that given the parents / this scenario, there is a higher likelihood of Cinnamon or Opaline Hens than Normal or Cin-Opaline Hens ? I would have thought they would have been the same chance ? Yes there is a higher likelihood because the genes carrying the Cinnamon and Opaline will sort independantly of each other. There is a 50/50 chance of getting one or the other but a minimal chance for the genes to cross over onto one chromosome and then be inherited together. The incidence of cross over in Opaline and Cinnamon is quite high, around the 30% mark from memory as they are approx 30 map units apart. Hi All, Sorry to be a pedantic so-and-so, but crossing over and recombination are pretty much the same things. Recombination is the result of crossing over as opposed to the return to normality or the status quo. Your definition suggests that the chromosomes re-unite at the same locus (recombine) where the reality is that the chromosomes will cross over or "recombine" at a somewhat random point , albeit the further from the chromosomes centromere, the greater the chance of crossing over I believe. Rip you are on the money with your percentages and I would say that 1 in 12 hens from this mating being cinnamon opaline is a relatively common event when referrring to crossing over events. Hope this helps. Cheers PT You can get pedantic if you like, I do the same from time to time. I wasn't actually putting forward a defination as such rather trying to explain what happens which is really hard when you have try and do it all with words. You are correct the further away from the Centromere the likelyhood is increased of cross over. The words cross over and recombination, athough similar and in a broad sense mean the same thing, in fact are used quite differently. Crossing over generally refers to the first event whereby the genes leave their place of residence, recombination is the second event whereby they find there way back. Not in exactly the same place as wence it came but rather in the location to which it belong on another choromosome. If it is a sex chromosome involved it has to recombine with like chromosome and if it is say non sex linked it has to recombine with the chromosome eqivalent it came from i.e. if the gene left chromosome 12 then it must return to another chromosome 12. It cannot randomly pick another chromosome. There is a place for that particular sequence to reside. If genes randomly ended up anywhere on a chromosome scientists would not have been able to map the DNA of humans, drosophilia, horses, chickens just to name a few. Edited December 10, 201014 yr by RIPbudgies
December 10, 201014 yr Thanks guys. I was following the logic up until RIP put the percentages down and used Light Green/ Opaline-Cinnamon II ?? What does this mean ? And Re-combination ? I've read about this Gene cross over which suggest that these two varieties link, so 50% of the daughters will be Cinnamon Opaline, the rest Normals ? (Assuming the Hen is a Normal)[/Quote] Crossing over is where the genes cross from one chormosome to another, re-combination is the reverse of that process. In order to find out what may happen you need type what type of crossover happened in the first place. Hence the term, Opaline Cinnamon-II. What this means is the cock birds carries the Opaline gene on one chromosome and the Cinnamon gene on the other. They are not linked i.e. on the same choromosome and therefore will not be passed on together at each choromosomal split. There is a small chance however over crossing over or recombination. This is where the two genes can occupy the same choromosome. When the two genes occupy the same chromosome it is thus written as Cinnamon Opaline-I or it can be written as Cinnamon-Opaline (the hyphen between the words denotes linkage, no hyphen no linkage). RIP are you saying that given the parents / this scenario, there is a higher likelihood of Cinnamon or Opaline Hens than Normal or Cin-Opaline Hens ? I would have thought they would have been the same chance ? Yes there is a higher likelihood because the genes carrying the Cinnamon and Opaline will sort independantly of each other. There is a 50/50 chance of getting one or the other but a minimal chance for the genes to cross over onto one chromosome and then be inherited together. The incidence of cross over in Opaline and Cinnamon is quite high, around the 30% mark from memory as they are approx 30 map units apart. Hi All, Sorry to be a pedantic so-and-so, but crossing over and recombination are pretty much the same things. Recombination is the result of crossing over as opposed to the return to normality or the status quo. Your definition suggests that the chromosomes re-unite at the same locus (recombine) where the reality is that the chromosomes will cross over or "recombine" at a somewhat random point , albeit the further from the chromosomes centromere, the greater the chance of crossing over I believe. Rip you are on the money with your percentages and I would say that 1 in 12 hens from this mating being cinnamon opaline is a relatively common event when referrring to crossing over events. Hope this helps. Cheers PT You can get pedantic if you like, I do the same from time to time. I wasn't actually putting forward a defination as such rather trying to explain what happens which is really hard when you have try and do it all with words. You are correct the further away from the Centromere the likelyhood is increased of cross over. The words cross over and recombination, athough similar and in a broad sense mean the same thing, in fact are used quite differently. Crossing over generally refers to the first event whereby the genes leave their place of residence, recombination is the second event whereby they find there way back. Not in exactly the same place as wence it came but rather in the location to which it belong on another choromosome. If it is a sex chromosome involved it has to recombine with like chromosome and if it is say non sex linked it has to recombine with the chromosome eqivalent it came from i.e. if the gene left chromosome 12 then it must return to another chromosome 12. It cannot randomly pick another chromosome. There is a place for that particular sequence to reside. If genes randomly ended up anywhere on a chromosome scientists would not have been able to map the DNA of humans, drosophilia, horses, chickens just to name a few. No Probs. You are correct when you describe that each time crossing over occurs it should ideally happen at a point equivalent to where it came from. When I refer to it being a random event, I refer to each crossing over event happening at a random point, i.e. each time a chromotid crosses it happens at a different point , not the same point every time. I beg to differ about the usage of the word recombination, but that is not important as we appear to be on the same page and it is just semantics. Cheers PT
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