OMIA:001677-9796 : Epidermolysis bullosa, junctionalis, LAMA3-related in Equus caballus (horse)

In other species: dog , taurine cattle

Categories: Integument (skin) phene

Links to possible relevant human trait(s) and/or gene(s) in OMIM: 226700 (trait) , 600805 (gene) , 245660 (trait) , 226650 (trait)

Mendelian trait/disorder: yes

Mode of inheritance: Autosomal recessive

Considered a defect: yes

Key variant known: yes

Year key variant first reported: 2009

Cross-species summary: Congenital blistering skin disease characterized by separation of the lamina lucida of the basement membrane zone. Blisters often occur in and around the mouth and on the limbs, leading in the latter case to separation of the hoof or nail from the corium (dermis).

Species-specific name: Also known as Epitheliogenesis imperfecta.

Molecular basis: By sequence analysis of three strong comparative candidate genes, Graves et al. (2009) identified a causal mutation as a "6589-bp deletion spanning exons 24-27 . . . in the LAMA3 gene in American Saddlebred foals" [OMIAvariantID:658].

Prevalence: Graves et al. (2009) reported that "nine of 175 randomly selected American Saddlebred foals from the 2007 foal crop were found to be carriers of the [deletion] mutation (frequency of 0.026)".

Breed: American Saddle Horse (Horse) (VBO_0000898).
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).

Associated gene:

Symbol Description Species Chr Location OMIA gene details page Other Links
LAMA3 laminin, alpha 3 Equus caballus 8 NC_009151.3 (48410496..48708623) LAMA3 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
658 American Saddle Horse (Horse) Epidermolysis bullosa, junctionalis, LAMA3-related LAMA3 deletion, gross (>20) Naturally occurring variant EquCab3.0 8 NC_009151.3:g.48678342_48684920del "6589-bp deletion spanning exons 24-27 . . . in the LAMA3 gene in American Saddlebred foals" 2009 19016681 Coordinates in EquCab3.0 kindly provided by Haley Rutstein, working under the guidance of Professor Ernie Bailey.

Cite this entry

Nicholas, F. W., Tammen, I., & Sydney Informatics Hub. (2024). OMIA:001677-9796: 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.

2009 Graves, K.T., Henney, P.J., Ennis, R.B. :
Partial deletion of the LAMA3 gene is responsible for hereditary junctional epidermolysis bullosa in the American Saddlebred Horse. Anim Genet 40:35-41, 2009. Pubmed reference: 19016681. DOI: 10.1111/j.1365-2052.2008.01795.x.
2005 Milenkovic, D., Mata, X., Chadi, S., Guérin, G. :
cDNA sequence of the horse (Equus caballus) LAMA3 gene and characterization of two intronic SNP markers. DNA Seq 16:468-73, 2005. Pubmed reference: 16287627. DOI: 10.1080/10425170500287674.
2003 Lieto, LD., Cothran, EG. :
The epitheliogenesis imperfecta locus maps to equine chromosome 8 in American Saddlebred horses. Cytogenet Genome Res 102:207-10, 2003. Pubmed reference: 14970704. DOI: 10.1159/000075750.
2002 Lieto, L.D., Swerczek, T.W., Cothran, E.G. :
Equine epitheliogenesis imperfecta in two American Saddlebred foals is a lamina lucida defect Vet Pathol 39:576-80, 2002. Pubmed reference: 12243468. DOI: 10.1354/vp.39-5-576.
1976 Crowell, W.A., Stephenson, C., Gosser, H.S. :
Epitheliogenesis imperfecta in a foal J Am Vet Med Assoc 168:56-8, 1976. Pubmed reference: 1245446.

Edit History

  • Created by Frank Nicholas on 09 Dec 2011
  • Changed by Frank Nicholas on 09 Dec 2011
  • Changed by Carrie Finno on 11 Dec 2013
  • Changed by Imke Tammen2 on 27 Mar 2024