OMIA:000963-9823 : Syndactyly in Sus scrofa (pig)

In other species: chicken , tammar wallaby , dog , domestic cat , taurine cattle , sheep , Swainson's hawk

Categories: Limbs / fins / digit / tail phene

Links to possible relevant human trait(s) and/or gene(s) in OMIM: 212780 (trait) , 186100 (trait) , 186200 (trait) , 186300 (trait) , 604270 (gene)

Mendelian trait/disorder: yes

Considered a defect: no

Key variant known: no

Cross-species summary: Fusion of the claws (cleats or digits). Occurs in one, two, three or (rarely) four legs.

Species-specific description: Facioli et al. (2021): "The swine mulefoot (SM) is a rare condition characterized by a non-cloven hoof due to the partial or total fusion of the phalanges. ... The swine mulefoot is a well-adapted animal to be raised in outdoor systems ... . In addition to that, animals with this characteristic tend to have higher lard content in their carcass. Currently, the mulefoot phenotype is an undesirable trait for industrial-scale swine production as this prioritizes intensive breeding systems with animal confinement on cement floors, and now those animals are at risk of extinction ..."

Inheritance: Facioli et al. (2021) "An experimental population was produced using a half-sib mating where the [Piau crossbred] male had the mulefoot phenotype and the females (n = 6) had cloven hoofs. The cross resulted in 27 (47%) animals with the mulefoot characteristic and 30 (53%) normal animals, indicating the possible dominant gene action."

Mapping: Facioli et al. (2021) "aimed to characterize the association between SNP and the mulefoot phenotype using a Genome-Wide Association Study (GWAS). ... . Animals were further genotyped using the Illumina PorcineSNP50k BeadChip, and SNPs were tested for associations. Twenty-nine SNPs located on the SSC15, SSC4, and SSCX were associated with the mulefoot phenotype (p-value <5 × 10-5). Six markers were found in the intronic regions of VWC2L, CATIP, PDK3, PCYT1B, and POLA1 genes. The marker rs81277626, on SSC15:116,886,110 bp, is located in the Von Willebrand Factor C Domain (VWC2L), a possible functional candidate gene. The VWC2L is part of a biological process involved with the bone morphogenetic protein (BMP) signaling pathway, previously associated with syndactyly in other species."

Breeds: Casco de Mula, Colombia (Pig) (VBO_0012556), Mulefoot, United States of America (Pig) (VBO_0013230), Piau, Brazil (Pig) (VBO_0012726).
Breeds in which the phene has been documented. (If a likely causal variant has been documented for the phene, see the variant table breeds in which the variant has been reported).

Cite this entry

Nicholas, F. W., Tammen, I., & Sydney Informatics Hub. (2022). OMIA:000963-9823: 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.

2021 Facioli, F.L., da Silva, A.N., Dos Santos, E.D., de Camargo, J., Warpechowski, M.B., da Oliveira Cruz, J., Lof, L.M., Zanella, R. :
From Mendel laws to whole genetic association study to decipher the swine mulefoot phenotype. Res Vet Sci 143:58-65, 2021. Pubmed reference: 34974356. DOI: 10.1016/j.rvsc.2021.12.009.
2016 Justolin, P.L., Rahal, S.C., Agostinho, F.S., Mamprim, M.J., Teixeira, C.R., Doiche, D.P., Babicsak, V.R. :
Radiographic and computed tomographic evaluation and gait analysis of Brazilian minipigs with syndactyly. Am J Vet Res 77:976-982, 2016. Pubmed reference: 27580109. DOI: 10.2460/ajvr.77.9.976.
2013 Madgwick, R., Forest, V., Beglane, F. :
Syndactyly in pigs: A review of previous research and the presentation of eight archaeological specimens. Int. J. Osteoarchaeol. 23:395-409, 2013.
1982 Ollivier, L., Sellier, P. :
Pig genetics: a review Annales de Genetique et de Selection Animale 14:481-544, 1982.
1972 Leipold, H.W., Dennis, S.M. :
Syndactyly in a pig Cornell Veterinarian 62:269-273, 1972. Pubmed reference: 4336933.
1953 Leinati, L., Telesforo, B. :
[Observations on a certain variety of malformation of the foot (Syndactylia) in pigs of the 'Casco de Mula' breed (Uniungular pigs) in Colombia] Proceedings of the Fifteenth International Veterinary Congress, Stockholm 2:907-913, 1953.
Leinati, L., Telesforo, B. :
[Observations on a certain variety of malformation of the foot (Syndactylia) in pigs of the 'Casco de Mula' breed (Uniungular pigs) in Colombia]: bibliography and discussion Proceedings of the Fifteenth International Veterinary Congress, Stockholm :359-360, 1953.
1921 Detlefsen, J.A., Carmichael, W.J. :
Inheritance of syndactylism, black and dilution in swine Journal of Agricultural Research 20:595-604, 1921.
1908 Simpson, Q.I., Simpson, J.P. :
Genetics in swine hybrids Science 27:941 only, 1908.
1889 Auld, R.C. :
Some cases of solid-hoofed hogs and two-toed horses American Naturalist 23:447-449, 1889.

Edit History

  • Created by Frank Nicholas on 06 Sep 2005
  • Changed by Imke Tammen2 on 14 Jan 2022