Genetics of the Rose comb

The Rose-comb Mutation in Chickens Constitutes a Structural Rearrangement Causing Both Altered Comb Morphology and Defective Sperm Motility


http://www.plosgenetics.org/article/info:doi/10.1371/journal.pgen.1002775

I have got to stop clicking on links just because they look interesting. Though they usually are interesting.

Here's todays find... being homozygous for a rose comb causes reduced fertility in the rooster. Your best producing rooster might carry an allele for a wild type comb (single comb) as he'd be heterozygous for the rose comb allele.

Well, except that there are two different alleles for the rose comb. R1 is the original, R2 is the second rose comb allele found. Test breeding shows that while R1R1 roosters have problems with fertility, R1R2 roosters do not!

Have fun reading, I just skimmed to the good parts

So the big question with RC fertility issues emerges out of White Wyandotte flocks in the first half of the 20th century. On a commercial scale, where it's all about crunching numbers and potential for loss, then this information might seem important. Primarily it affects sperm storage pre-fertilization, which might be of importance in commercial flock mating scenarios.

However, for the small-scale breeder there is no concern with rose combs at all. Most small-scale breeders work on a level that promotes regular insemination which reduces any danger of sperm storage issues.

Correct- though if you are having fertility problems, it probably means you can still use the rooster. If he has other alleles you want to keep, breed him so that your next generation rooster is R1R2 or R1r. Though I'm not sure how you'd know if it's an R2 hen!

Yes, the article probably has very limited practical value to the backyard chicken raiser but it is (to me) interesting. That there are two allele for the same comb type was worth reading. Makes you wonder if the two alleles have a different affect on more than just comb and fertility.

Well, sure, it's all interesting. I just posted here so that folks wouldn't shy away from adopting RC breeds with the erroneous assumption that they would somehow have fertility issues.

Yellow House Farm said:

Well, sure, it's all interesting.  I just posted here so that folks wouldn't shy away from adopting RC breeds with the erroneous assumption that they would somehow have fertility issues.  

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Very good point.

If you test enough for genetic problems you'll find some. Everyone has some *bad* genes.

Indeed, apparently Pea combs are genetically attached to breast blisters, and single combs are prone to frostbite. V combs are fairly "risk" free.

And more pubmed etc articles on rose comb genetics. No need to read them all, no one will test you Lowered fertility in some roosters with a rose comb has been noted in peer-reviewed articles for at least 50years.

2012 Imsland, F., Feng, C., Boije, H., Bed'hom, B., Fillon, V., Dorshorst, B., Rubin, C-J., Liu, R., Gao, Y., Gu, X., Wang, Y., Gourichon, D., Zody, M.C., Zecchin, W., Vieaud, A., Tixier-Boichard, M., Hu, X., Hallböök, F., Li, N., Andersson, L. :
The Rose-comb Mutation in Chickens Constitutes a Structural Rearrangement Causing Both Altered Comb Morphology and Defective Sperm Motility PLoS Genetics 8(6):e1002775, 2012. Pubmed reference: 22761584. DOI: 10.1371/journal.pgen.1002775.
Wragg, D., Mwacharo, J.M., Alcalde, J.A., Hocking, P.M., Hanotte, O. :
Analysis of genome-wide structure, diversity and fine mapping of Mendelian traits in traditional and village chickens. Heredity (Edinb) 109:6-18, 2012. Pubmed reference: 22395157. DOI: 10.1038/hdy.2012.9.
2010 Dorshorst, B., Okimoto, R., Ashwell, C. :
Genomic regions associated with dermal hyperpigmentation, polydactyly and other morphological traits in the Silkie chicken. J Hered 101:339-50, 2010. Pubmed reference: 20064842. DOI: 10.1093/jhered/esp120.
2008 Vaez, M., Follett, SA., Bed'hom, B., Gourichon, D., Tixier-Boichard, M., Burke, T. :
A single point-mutation within the melanophilin gene causes the lavender plumage colour dilution phenotype in the chicken. BMC Genet 9:7, 2008. Pubmed reference: 18197963. DOI: 10.1186/1471-2156-9-7.
1996 Mclean, D.J., Froman, D.P. :
Identification of a sperm cell attribute responsible for subfertility of roosters homozygous for the rose comb allele Biology of Reproduction 54:168-172, 1996. Pubmed reference: 8838014.
1994 Kirby, J.D., Engel, H.N., Froman, D.P. :
Analysis of Subfertility Associated with Homozygosity of the Rose Comb Allele in the Male Domestic Fowl Poultry Science 73:871-878, 1994. Pubmed reference: 8072931.
1993 Shoffner, R.N., Otis, J.S., Garwood, V.A. :
Association of Dominant Marker Traits and Metric Traits in Chickens Poultry Science 72:1405-1410, 1993. Pubmed reference: 8378215.
1992 Froman, D.P., Kirby, J.D., Alaghbari, A.M. :
Analysis of the Combined Effect of the Spermatozoal Degeneration Allele (Sd) and Homozygosity of the Rose Comb Allele (R) on the Duration of Fertility of Roosters (Gallus domesticus) Poultry Science 71:1939-1942, 1992. Pubmed reference: 1437982.
1981 Petitjean, M., Servouse, M. :
Comparative study of some characteristics of the semen of RR (rose comb) or rr (single comb) cockerels. Reprod Nutr Dev 21:1085-93, 1981. Pubmed reference: 6218547.
1974 Etches, RJ., Buckland, RB., Hawes, RO. :
The effect of the genes for rose comb and polydactyly on sperm transport in the hen's oviduct. Poult Sci 53:422-4, 1974. Pubmed reference: 4833050.
1972 Brumbaugh, JA., Chatterjee, G., Hollander, WF. :
Adendritic melanocytes: a mutation in linkage group II of the fowl. J Hered 63:19-25, 1972. Pubmed reference: 5019540.
1971 Crawford, R.D. :
Rose comb and fertility in silver Spangled Hamburgs. Poult Sci 50:867-9, 1971. Pubmed reference: 5569770.
1969 Buckland, R.B., Wilcox, F.H., Shaffner, C.S. :
Influence of homozygosity for rose comb on fumarase, aconitase, isocitric dehydrogenase and malic dehydrogenase activity in spermatozoa of the domestic fowl (Gallus domesticus). J Reprod Fertil 18:89-95, 1969. Pubmed reference: 5791687.
1968 Buckland, RB., Hawes, RO. :
Comb type and reproduction in the male fowl segregation of the rose and pea comb genes. Can J Genet Cytol 10:395-400, 1968. Pubmed reference: 5699835.
1965 Crawford, R.D., Smyth, J.R. :
The influence of comb genotype on mating behaviour in the domestic fowl Poultry Science 44:115-122, 1965. Pubmed reference: 14336869.
Crawford, R.D., Smyth, J.R. :
Infertility and action of the genes for rose comb in the domestic fowl Biological Abstracts 46:24-, 1965.
1964 Crawford, R.D., Smyth, J.R. :
Semen quality and the gene for rose comb in the domestic fowl Poultry Science 43:1551-1557, 1964.
Crawford, R.D., Smyth, J.R. :
Infertility and action of the gene for Rose comb in the domestic fowl Can J Genet Cytol 259:298-303, 1964. Pubmed reference: 14208710.
Crawford, R.D., Smyth, R.J. :
Studies of the relationship between fertility and the gene for rose comb in the domestic fowl. I. The relationship between comb genotype and fertility Poultry Science 43:1009-1017, 1964.
1963 Crawford, R.D., Merritt, E.S. :
The relationship between rose comb and reproduction in the domestic fowl Canadian Journal of Genetics and Cytology 5:89-95, 1963. Pubmed reference: 14023733.
Merat, P. :
[Abnormal segregation for the alleles 'single comb' and 'rose comb' in the fowl. II. rr male x Rr female] Annales de Biologie Animale, Biochimie, Biophysique 3:59-64, 1963.
Merat, P. :
Abnormal segregations for the alleles 'single comb' and 'Rose comb' in the domestic fowl Genetics Today. Proceedings of the Eleventh International Congress of Genetics, The Hague 1:259 Abstract, 1963.
Merat, P. :
[Abnormal segregation for the alleles 'single comb' and 'rose comb' in the fowl. IV. Combined discussion on the three tupes of cross, RrXrr. rrXRr and RrXRr] Annales de Biologie Animale, Biochimie, Biophysique 3:133-141, 1963.

Indeed, with shorter shelf life inside the hens, waiting to fertilize eggs, yet none of this effects small-scale operations in an important way.

Yellow House Farm said:

Indeed, with shorter shelf life inside the hens, waiting to fertilize eggs, yet none of this effects small-scale operations in an important way.

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Might, might not. Worth noting, especially if you have two rooster with same hens, one rose comb, one not.

Well, in an SOP scenario that probably wouldn't occur. Even then, if the right ratios are maintained, the chances of incurring infertility are slim.