OMIA:000380-9031 : Feathering, Z-linked in Gallus gallus (chicken)

In other species: helmeted guineafowl , turkey

Categories: Integument (skin) phene

Links to possible relevant human trait(s) and/or gene(s) in OMIM: 176761 (gene)

Mendelian trait/disorder: yes

Mode of inheritance: Z-linked

Considered a defect: yes

Key variant known: yes

Year key variant first reported: 2008

Species-specific symbol: K(s)

Species-specific description: The difference between K- (slow-feathering) and kk (fast-feathering) chickens is discernible immediately after hatching. This difference has been exploited as a far simpler means of sexing day-old chickens than the traditional method of vent sexing.

History: The (Z-linked) inheritance of this trait was reported by Serebrosky (1922) as already well known, but without any relevant citation.

Inheritance: The locus is Z-linked, with slow-feathering being dominant to fast or rapid feathering (the wild type)

Markers: Smith and Crittenden (1988) reported that the K allele "is associated with an endogenous provirus gene, ev21". Smith and Fadly (1994) concluded that "ev21 and K appear to be less than .3 cM apart".

Molecular basis: Elferink et al. (2008) reported a likely causal variant as "a duplication at the K allele and sequence analysis of the breakpoint junction indicated a tandem duplication of 176,324 basepairs. The tandem duplication of this region results in the partial duplication of two genes; the prolactin receptor [PRLR] and the gene encoding sperm flagellar protein 2 [SPEF2]. Sequence analysis revealed that the duplication is similar in Broiler and White Leghorn. In addition, twelve late feathering animals, including Broiler, White Leghorn, and Brown Layer lines, contained a 78 bp breakpoint junction fragment, indicating that the duplication is similar in all breeds." Luo et al. (2012) reported evidence "that increasing PRLR expression that resulted from the special variant on chicken Z chromosome caused the late-feathering phenotype" Bu et al. (2013) reported evidence that the partially duplicated PRLR "is predicted to encode a membrane-spanning receptor of 683 amino acids, which is nearly identical to the original PRLR, except for its lack of a 149-amino acid C-terminal tail." Liu et al. (2020): Research by two master’s students (J. Li (2012) and Z. Huang (2014) cited by Liu et al. 2020) “found that many EF [early-feathering] feathering chicks had the tandem duplication in Chinese native chicken breeds, which suggested that dPRLR [duplicated prolactin receptor] was not the determinant of the LF [late-feathering] feathering phenotype. Luo et al. (2012) found that the expression level of the prolactin receptor (PRLR) gene in LF chickens was 1.78 times higher than that in EF chickens. However, Zhao et al. (2016) reported that there was no significant difference between the PRLR expression levels of the EF and LF chicks in their study. Because there was an extremely significant difference in the expression level of SPEF2, but not of PRLR between the EF and LF chickens, Zhao et al. (2016) suggested that SPEF2 should be a good candidate gene for the chicken feather rate phenotype rather than PRLR.” Liu et al. (2020) conducted a genome-wide association study (GWAS) in Shouguang chicks “to map candidate genomic regions related to the feather rate” and analysed “RNA sequencing data from the hair follicle tissue of the EF and LF samples. …. The sperm flagellar 2 gene (SPEF2) and prolactin receptor (PRLR) gene were the only two overlapping genes between the results of GWAS and differential expression analysis, which implies that SPEF2 and PRLR are possible candidate genes for the formation of the chicken feathering phenotype in the present study.”

Clinical features: The K(s) mutation is a mixed blessing. While it is obviously advantageous in terms of the slow-feathering phenotype it has created, it is disadvantageous because it produces infectious viral particles (called endogenous viruses). These viruses are transmitted congenitally from hens with K(s) to all of their offspring. This does not seem to harm those offspring that also inherit K(s), i.e. the slow-feathering offspring. But in the offspring that have not inherited K(s) (i.e. the fast-feathering offspring), the presence of endogenous viral particles induces immunological tolerance to the virus, which renders the chickens unable to mount an effective immune response aganist exogenous viral particles, resulting in poorer performance and increased mortality due to tumours induced by the exogenous virus. Fortunately, there are various ways to overcome at least some of this disadvantage, such as vaccination of the slow-feathering dams, who then provide protection to their offspring via the transfer of maternal antibodies.

Genetic testing: Elferink et al. (2008): "The breakpoint junction was used to develop a TaqMan-based quantitative PCR test to allow distinction between homozygous and heterozygous late feathering males. In total, 85.3% of the animals tested were correctly assigned, 14.7% were unassigned and no animals were incorrectly assigned." Takenouchi et al. (2018) provided evidence that "regarding LF [late feathering] expression, the results indicated that ID [incomplete duplication of the prolactin receptor (PRLR) and sperm flagellar protein 2 (SPEF2) genes] is responsible, but ev21 [endogenous ev21 gene] is not required, which led them to recommend that "Henceforth, ID should be used as a molecular marker to detect LF [later feathering] birds instead of ev21." Based on the findings reported by Liu et al. (2020) further research will be required to identify any variation within the duplication that is causal for the feathering phenotype to develop reliable genetic testing for all breeds. Shen et al. (2023): developed a multiplex PCR test to identify early feathering (EF) and late feathering (LF) homozygote, and heterozygote chicken. The authors tested "413 chickens of six native Chinese breeds with this method. The identification was consistent with the sex and phenotype records of the chickens. ... In order to further verify the accuracy of this test in distinguishing homozygote and heterozygote males, 152 LF males were mated with EF females, and the results of the offspring's phenotypes were consistent with our expectations. Our results support tandem duplication as molecular markers of LF, and this new test is applicable to all LF chickens associated with tandem duplication."

Associated gene:

Symbol Description Species Chr Location OMIA gene details page Other Links
PRLR prolactin receptor Gallus gallus Z NC_052572.1 (11350251..11159196) PRLR Homologene, Ensembl , NCBI gene


By default, variants are sorted chronologically by year of publication, to provide a historical perspective. Readers can re-sort on any column by clicking on the column header. Click it again to sort in a descending order. To create a multiple-field sort, hold down Shift while clicking on the second, third etc relevant column headers.

WARNING! Inclusion of a variant in this table does not automatically mean that it should be used for DNA testing. Anyone contemplating the use of any of these variants for DNA testing should examine critically the relevant evidence (especially in breeds other than the breed in which the variant was first described). If it is decided to proceed, the location and orientation of the variant sequence should be checked very carefully.

Since October 2021, OMIA includes a semiautomated lift-over pipeline to facilitate updates of genomic positions to a recent reference genome position. These changes to genomic positions are not always reflected in the ‘acknowledgements’ or ‘verbal description’ fields in this table.

OMIA Variant ID Breed(s) Variant Phenotype Gene Allele Type of Variant Source of Genetic Variant Reference Sequence Chr. g. or m. c. or n. p. Verbal Description EVA ID Year Published PubMed ID(s) Acknowledgements
719 Feathering, Z-linked PRLR duplication Naturally occurring variant Z The tandem duplication of this region results in the partial duplication of two genes; the prolactin receptor and the gene encoding sperm flagellar protein 2. 2008 18713476

Cite this entry

Nicholas, F. W., Tammen, I., & Sydney Informatics Hub. (2023). OMIA:000380-9031: Online Mendelian Inheritance in Animals (OMIA) [dataset].


Note: the references are listed in reverse chronological order (from the most recent year to the earliest year), and alphabetically by first author within a year.

2024 Qiu, M., Zhang, Z., Zhu, S., Liu, S., Peng, H., Xiong, X., Chen, J., Hu, C., Yang, L., Song, X., Xia, B., Yu, C., Yang, C. :
Transcriptome sequencing and mass spectrometry reveal genes involved in the non-Mendelian inheritance-mediated feather growth rate in chicken. Biochem Genet , 2024. Pubmed reference: 38280152. DOI: 10.1007/s10528-023-10643-y.
2023 Shen, Q., Li, J., Bao, H., Wu, C. :
Identification of duplication genotypes of the feathering rate gene in chicken by a multiplex PCR following electrophoresis and/or Sanger sequencing. Animals (Basel) 13:1091, 2023. Pubmed reference: 36978632. DOI: 10.3390/ani13061091.
2022 Fathi, M.M., Galal, A., Radwan, L.M., Abou-Emera, O.K., Al-Homidan, I.H. :
Using major genes to mitigate the deleterious effects of heat stress in poultry: an updated review. Poult Sci 101:102157, 2022. Pubmed reference: 36167017. DOI: 10.1016/j.psj.2022.102157.
2020 Liu, X., Wu, Z., Li, J., Bao, H., Wu, C. :
Genome-wide association study and transcriptome differential expression analysis of the feather rate in Shouguang chickens. Front Genet 11:613078, 2020. Pubmed reference: 33414812. DOI: 10.3389/fgene.2020.613078.
2018 Derks, M.F.L., Herrero-Medrano, J.M., Crooijmans, R.P.M.A., Vereijken, A., Long, J.A., Megens, H.J., Groenen, M.A.M. :
Early and late feathering in turkey and chicken: same gene but different mutations. Genet Sel Evol 50:7, 2018. Pubmed reference: 29566646. DOI: 10.1186/s12711-018-0380-3.
Takenouchi, A., Toshishige, M., Ito, N., Tsudzuki, M. :
Endogenous viral gene ev21 is not responsible for the expression of late feathering in chickens. Poult Sci 97:403-411, 2018. Pubmed reference: 29253229. DOI: 10.3382/ps/pex345.
2016 Zhao, J., Yao, J., Li, F., Yang, Z., Sun, Z., Qu, L., Wang, K., Su, Y., Zhang, A., Montgomery, S.A., Geng, T., Cui, H. :
Identification of candidate genes for chicken early- and late-feathering Poultry Science 95:1498-1503, 2016. DOI: 10.3382/ps/pew131.
2013 Bu, G., Huang, G., Fu, H., Li, J., Huang, S., Wang, Y. :
Characterization of the novel duplicated PRLR gene at the late-feathering K locus in Lohmann chickens. J Mol Endocrinol 51:261-76, 2013. Pubmed reference: 23940279. DOI: 10.1530/JME-13-0068.
2012 Luo, C., Shen, X., Rao, Y., Xu, H., Tang, J., Sun, L., Nie, Q., Zhang, X. :
Differences of Z chromosome and genomic expression between early- and late-feathering chickens. Mol Biol Rep 39:6283-8, 2012. Pubmed reference: 22297689. DOI: 10.1007/s11033-012-1449-7.
2009 Khosravinia, H. :
Effect of the slow (K) or rapid (k+) feathering gene on carcass related traits of broiler chickens selected for breast and thighs weight. Genetika 45:112-8, 2009. Pubmed reference: 19239105.
2008 Elferink, MG., Vallee, AA., Jungerius, AP., Crooijmans, RP., Groenen, MA. :
Partial duplication of the PRLR and SPEF2 genes at the late feathering locus in chicken. BMC Genomics 9:391, 2008. Pubmed reference: 18713476. DOI: 10.1186/1471-2164-9-391.
2006 Swaggerty, CL., He, H., Genovese, KJ., Kaiser, P., Pevzner, IY., Kogut, MH. :
The feathering gene is linked to degranulation and oxidative burst not cytokine/chemokine mRNA expression levels or Salmonella enteritidis organ invasion in broilers. Avian Pathol 35:465-70, 2006. Pubmed reference: 17121735. DOI: 10.1080/03079450601028829.
2003 Kalinowski, A., Moran, E.T., Wyatt, C.L. :
Methionine and cystine requirements of slow- and fast-feathering broiler males from three to six weeks of age. Poult Sci 82:1428-37, 2003. Pubmed reference: 12967257.
Kalinowski, A., Moran, E.T., Wyatt, C. :
Methionine and cystine requirements of slow- and fast-feathering male broilers from zero to three weeks of age. Poult Sci 82:1423-7, 2003. Pubmed reference: 12967256.
Swaggerty, C.L., Pevzner, I.Y., Ferro, P.J., Crippen, T.L., Kogut, M.H. :
Association between in vitro heterophil function and the feathering gene in commercial broiler chickens. Avian Pathol 32:483-8, 2003. Pubmed reference: 14522703. DOI: 10.1080/0307945031000154071.
2002 Ozkan, S., Smith, W.K., Bath, H.M. :
The development of thermal resistance of the feather coat in broilers with different feathering genotypes and feeding regimes British Poultry Science 43:472-481, 2002. Pubmed reference: 12195808. DOI: 10.1080/00071660120103765.
2001 Fotsa, J.C., Merat, P., Bordas, A. :
Effect of the slow (K) or rapid (k(+)) feathering gene on body and feather growth and fatness according to ambient temperature in a Leghorn X brown egg type cross Genetics Selection Evolution 33:659-670, 2001.
Hamoen, F.F., Van Kaam, J.B., Groenen, M.A., Vereijken, A.L., Bovenhuis, H. :
Detection of genes on the Z-chromosome affecting growth and feathering in broilers. Poult Sci 80:527-34, 2001. Pubmed reference: 11372699. DOI: 10.1093/ps/80.5.527.
1999 Bitgood, J.J. :
Linkage relationships of the Z-linked silver, slow feathering, and pop-eye loci Poultry Science 78:1100-1101, 1999. Pubmed reference: 10472834.
1997 Fadly, A.M., Smith, E.J. :
Role of contact and genetic transmission of endogenous VIRUS-21 in the susceptibility of chickens to avian leukosis virus infection and tumors Poultry Science 76:968-973, 1997. Pubmed reference: 9200232.
Tixierboichard, M., Boulliourobic, A., Morisson, M., Coquerelle, G., Horst, P., Benkel, B. :
A deleted retroviral insertion at the EV21-K complex locus in Indonesian chickens Poultry Science 76:733-742, 1997. Pubmed reference: 9154627.
1996 Wimmers, K., Schmidt, P., Vallezarate, A., Brockmann, G., Horst, P., Schwerin, M. :
Molecular analysis of a new variant of the EV21 insertion/k-gene complex in the super slow feathering nunukan chicken Journal of Animal Breeding & Genetics-Zeitschrift fur Tierzuchtung und Zuchtungsbiologie 113:323-329, 1996.
1995 Iraqi, F., Smith, E.J. :
Organization of the sex-linked late-feathering haplotype in chickens Animal Genetics 26:141-146, 1995. Pubmed reference: 7793680.
Iraqi, F., Robinson, D., Smith, E.J. :
A restriction enzyme map of the sex-linked late-feathering locus of chickens Poultry Science 74:1515-1519, 1995. Pubmed reference: 7501596.
1994 Iraqi, F., Smith, E.J. :
Determination of the Zygosity of ev21-K in Late-Feathering Male White Leghorns Using the Polymerase Chain Reaction Poultry Science 73:939-946, 1994. Pubmed reference: 7937481.
Smith, E.J., Fadly, A.M. :
Male-mediated venereal transmission of endogenous avian leukosis virus. Poult Sci 73:488-94, 1994. Pubmed reference: 8202427. DOI: 10.3382/ps.0730488.
1993 Ajang, O.A., Prijono, S., Smith, W.K. :
Effect of Dietary Protein Content on Growth and Body Composition of Fast and Slow Feathering Broiler Chickens (Erratum) British Poultry Science 34:627-628, 1993.
Ajang, O.A., Prijono, S., Smith, W.K. :
Effect of Dietary Protein Content on Growth and Body Composition of Fast and Slow Feathering Broiler Chickens British Poultry Science 34:73-91, 1993.
Smith, E.J., Nelsen, T.C. :
Effect of Tumor Virus Susceptibility Alleles on the Late- Feathering Gene K on Early Growth of White Leghorns Poultry Science 72:1400-1404, 1993. Pubmed reference: 8378214.
1992 Amad, A., Poetschke, J., Müller, I., Chhum Pith, L. :
[Differentiation of fattening and slaughtering performance and carcass quality of broiler genotypes with and without the dwarf factor and fast or slow feathering under heat stress]. Beitr Trop Landwirtsch Veterinarmed 30:407-25, 1992. Pubmed reference: 1340754.
Boulliou, A., Lepennec, J.P., Hubert, G., Donal, R., Smiley, M. :
The Endogenous Retroviral ev21 Locus in Commercial Chicken Lines and Its Relationship with the Slow-Feathering Phenotype (K) Poultry Science 71:38-46, 1992. Pubmed reference: 1347168.
O'Sullivan, N.P., Dunnington, E.A., Siegel, P.B. :
Feed Intake, Utilization, and the Residual Component in Early- Feathering and Late-Feathering Broiler Breeder Dams Journal of Animal Breeding and Genetics - Zeitschrift Fur Tierzuchtung und Zuchtungsbiologie 109:197-206, 1992.
Tsiagbe, V.K., Harper, A.E., Sunde, M.L. :
A Feather-Sexed Strain of Laying Hens Was More Responsive to Dietary Supplements of Choline and Methionine Than a Vent- Sexed Strain Poultry Science 71:1271-1276, 1992. Pubmed reference: 1523176.
1991 Fadly, A.M., Smith, E.J. :
Influence of Maternal Antibody on Avian Leukosis Virus Infection in White Leghorn Chickens Harboring Endogenous Virus-21 (EV21) Avian Diseases 35:443-451, 1991. Pubmed reference: 1659362.
Gavora, J.S., Kuhnlein, U., Crittenden, L.B., Spencer, J.L., Sabour, M.P. :
Endogenous Viral Genes - Association with Reduced Egg Production Rate and Egg Size in White Leghorns Poultry Science 70:618-623, 1991. Pubmed reference: 1646446.
Levin, I., Smith, E.J. :
Association of a Chicken Repetitive Element with the Endogenous Virus-21 Slow-Feathering Locus Poultry Science 70:1948-1956, 1991. Pubmed reference: 1685775.
O'Sullivan, N.P., Dunnington, E.A., Smith, E.J., Gross, W.B., Siegel, P.B. :
Performance of Early and Late Feathering Broiler Breeder Females with Different Feeding Regimens British Poultry Science 32:981-995, 1991. Pubmed reference: 1664781. DOI: 10.1080/00071669108417423.
O'Sullivan, N.P., Dunnington, E.A., Siegel, P.B. :
Growth and Carcass Characteristics of Early-Feathering and Late-Feathering Broilers Reared Under Different Feeding Regimens Poultry Science 70:1323-1332, 1991.
Smith, E.J., Fadly, A.M., Levin, I., Crittenden, L.B. :
The Influence of ev6 on the Immune Response to Avian Leukosis Virus Infection in Rapid-Feathering Progeny of Slow- Feathering and Rapid-Feathering Dams Poultry Science 70:1673-1678, 1991. Pubmed reference: 1656418.
Smith, E.J., Levin, I. :
Application of a Locus-Specific DNA Hybridization Probe in the Analysis of the Slow-Feathering Endogenous Virus Complex of Chickens Poultry Science 70:1957-1964, 1991. Pubmed reference: 1685776.
1990 Levin, I., Smith, E.J. :
Molecular Analysis of Endogenous Virus Ev21-Slow Feathering Complex of Chickens .1. Cloning of Proviral-Cell Junction Fragment and Unoccupied Integration Site Poultry Science 69:2017-2026, 1990. Pubmed reference: 1982353.
Smith, E.J., Fadly, A.M., Crittenden, L.B. :
Interactions Between Endogenous Virus Loci Ev6 and Ev21 .1. Immune Response to Exogenous Avian Leukosis Virus Infection Poultry Science 69:1244-1250, 1990. Pubmed reference: 2172951.
Smith, E.J., Fadly, A.M., Crittenden, L.B. :
Interactions Between Endogenous Virus Loci Ev6 and Ev21 .2. Congenital Transmission of Ev21 Viral Product to Female Progeny from Slow-Feathering Dams Poultry Science 69:1251-1256, 1990. Pubmed reference: 2172952.
1989 Machal, L., Jerabek, S., Hampl, A. :
The production of coloursexing laying hens of domestic fowl when using the locus 'k' 8th International Symposium on Current Problems of Avian Genetics, Smolenice :251-254, 1989.
1988 Bacon, L.D., Smith, E., Crittenden, L.B., Havenstein, G.B. :
Association of the slow feathering (K) and an endogenous viral (ev21) gene on the Z chromosome of chickens Poultry Science 67:191-197, 1988. Pubmed reference: 2837753.
Merkley, J.W., Lowe, P.C. :
Association of rate-of-feathering genotypes in broilers with production and carcass composition traits. 2. Effect of genotypes and diet on processing traits and lipid deposition Poultry Science 67:914-919, 1988. Pubmed reference: 3413016.
Smith, E.J., Crittenden, L.B. :
Genetic cellular resistance to subgroup E avian leukosis virus in slow-feathering dams reduces congenital transmission of an endogenous retrovirus encoded at locus ev21 Poultry Science 67:1668-1673, 1988. Pubmed reference: 3241774.
Smith, E.J., Fadley, A.M. :
Influence of congenital transmission of endogenous virus-21 on the immune response to avian leukosis virus infection and the incidence of tumors in chickens Poultry Science 67:1674-1679, 1988. Pubmed reference: 2853868.
1987 Dunnington, E.A., Siegel, P.B., Katanbaf, M.N., Gross, W.B. :
Response of early and late feathering broilers to various stressors Poultry Science 66:168-170, 1987. Pubmed reference: 3575233.
1986 Bacon, L.D., Fadly, A.M., Crittenden, L.B. :
Absence of influence on immune competence by the sex-linked gene (K) determining slow feathering in White Leghorn chickens Avian Diseases 30:751-760, 1986. Pubmed reference: 3814012.
Dunnington, E.A., Siegel, P.B. :
Feather weight of early (k+) and late (K) feathering young adult broilers Poultry Science 65:1863-1865, 1986.
Dunnington, E.A., Siegel, P.B. :
Sex-linked feathering alleles (K, k+) in pullets of diverse backgrounds. 3. Age at first egg, egg production and antibody production Archiv fur Geflugelkunde 51:70-72, 1986.
Dunnington, E.A., Siegel, P.B., Gross, W.B. :
Sex-linked feathering alleles (K, k+) in chickens of diverse genetic backgrounds. Avian Pathol 15:139-48, 1986. Pubmed reference: 18766512. DOI: 10.1080/03079458608436273.
Garcia, A.J. :
[Sexing day-old chicks on the basis of sex-linked genes. Current trends] Revista Cubana de Ciencias Avicolas 13:13-32, 1986.
Lowe, P.C., Merkley, J.W. :
Association of genotypes for rate of feathering in broilers with production and carcass composition traits. Effect of genotypes, sex, and diet on grwoth and feed conversion Poultry Science 65:1853-1858, 1986.
Smith, E.J., Crittenden, L.B. :
Endogenous viral genes in a slow-feathering line of White Leghorn chickens. Avian Pathol 15:395-406, 1986. Pubmed reference: 18766541. DOI: 10.1080/03079458608436302.
1985 Bitgood, JJ. :
Additional linkage relationships within the Z chromosome of the chicken. Poult Sci 64:2234-8, 1985. Pubmed reference: 4095061.
Bondarenko, Y.Y. :
Genetical variability for types of feathering in day-old chicks :256-260, 1985.
1984 Harris, D.L., Garwood, V.A., Lowe, P.C., Hester, P.Y., Crittenden, L.B., Fadly, A.M. :
Influence of sex-linked feathering phenotypes of parents and progeny upon lymphoid leukosis virus infection status and egg production. Poult Sci 63:401-13, 1984. Pubmed reference: 6326072.
1983 Rao, G.V. :
The development of a sex-linked slow-feathering White Leghorn strain by gene transfer from an Indian indigenous breed. Br Poult Sci 24:251-4, 1983. Pubmed reference: 6883154. DOI: 10.1080/00071668308416736.
1980 Touchburn, S.P., Guillaume, J., Leclercq, B., Blum, J.C. :
Lipid and energy metabolism in chicks affected by dwarfism (dw) and Naked-neck (Na). Poult Sci 59:2189-97, 1980. Pubmed reference: 7465494.
1976 Telloni, RV., Jaap, RG., Fechheimer, NS. :
Cytogenetic and phenotypic effects of a chromosomal rearrangement involving the Z-chromosome and micro-chromosome in the chicken. Poult Sci 55:1886-96, 1976. Pubmed reference: 995812.
1975 Somes, R.G. :
Pleiotrophic effects of the sex-linked delayed feathering gene, K-n, in the chicken. Poult Sci 54:208-16, 1975. Pubmed reference: 1135127. DOI: 10.3382/ps.0540208.
Zvonova, L.N. :
The use of k gene for maternal form broiler parent production :234-238, 1975.
1970 Collins, WM., Teeri, AE., Kahn, AC., Zervas, NP., Costantino, RF. :
The influence of sex-linked barring and rate of feathering genes, and of stock, upon egg riboflavin and vitamin B12. Poult Sci 49:432-9, 1970. Pubmed reference: 5448671.
1969 Carte, I.F., Smith, J.H. :
Degree of linkage between the silver plumage (S) and slow juvenile feathering (K) loci. Poult Sci 48:343-344, 1969. Pubmed reference: 5389848.
Somes, R.G. :
Delayed feathering, a third allele at the K locus of the domestic fowl. J Hered 60:281-6, 1969. Pubmed reference: 5366322.
1968 Collins, WM., Kahn, AC., Teeri, AE., Zervas, NP., Ostantino, RF. :
The effect of sex-linked barring and rate of feathering genes, and of stock, upon egg yolk cholesterol. Poult Sci 47:1518-26, 1968. Pubmed reference: 5750110.
1959 Wessels, J.P.H. :
[Linkage between silver colour and late feathering in fowls] South African Journal of Agricultural Science 2:357-361, 1959.
1957 Siegel, P.B., Mueller, C.D., Craig, J.V. :
Some phenotypic differences among homozygous, heterozygous, and hemizygous late feathering chicks. Poultry Science 36:232-239, 1957.
1949 Warren, DC. :
Linkage relations of autosomal factors in the fowl. Genetics 34:333-50, 1949. Pubmed reference: 17247319.
1938 Warren, D.C. :
Mapping the genes of the fowl (abstract) Genetics 23:174 only, 1938. DOI: 10.1093/genetics/23.1.139.
1933 Macarthur, J.W. :
Sex-linked genes in the fowl. Genetics 18:210-20, 1933. Pubmed reference: 17246689.
1929 Danforth, C.H. :
Two Factors Influencing Feathering in Chickens. Genetics 14:256-69, 1929. Pubmed reference: 17246575.
1928 Warren, D.C. :
Sex-linked characters of poultry. Genetics 13:421-33, 1928. Pubmed reference: 17246558. DOI: 10.1093/genetics/13.5.421.
1925 Warren, D.C. :
Inheritance of rate of feathering in poultry Journal fo Heredity 16:13-18, 1925.
1922 Serebrosky, A.S. :
Crossing-over involving three sex-linked genes in chickens. American Naturalist 56:571-572, 1922.

Edit History

  • Created by Frank Nicholas on 12 Sep 2005
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