OMIA:002500-9796 : Azoospermia in Equus caballus (horse)

Categories: Reproductive system phene

Links to MONDO diseases: No links.

Mendelian trait/disorder: no

Considered a defect: yes

Key variant known: yes

Cross-species summary: Absence of sperm in the ejaculate

Species-specific description: Castaneda et al. (2021) report "a detailed molecular cytogenetic analysis of a reciprocal translocation between horse (ECA) chromosomes Y and 13 in a Friesian stallion with complete meiotic arrest and azoospermia. ... One resulting derivative chromosome, Y;13p, comprises of ECAY heterochromatin (ETSTY7 array), a small single copy and partial Y multicopy region, and ECA13p. Another derivative chromosome 13q;Y comprises of ECA13q and most of the single copy ECAY, the pseudoautosomal region and a small part of the Y multicopy region. A copy number (CN) analysis of select ECAY multicopy genes shows that the Friesian stallion has significantly (p < 0.05) reduced CNs of TSPY, ETSTY1, and ETSTY5, suggesting that the translocation may not be completely balanced, and genetic material is lost."

Genetic engineering: Unknown
Have human generated variants been created, e.g. through genetic engineering and gene editing

Breed: Friesian (Horse) (VBO_0000969).
Breeds in which the phene has been documented. For breeds in which a likely causal variant has been documented, see the variant table below

Cite this entry

Nicholas, F. W., Tammen, I., & Sydney Informatics Hub. (2022). OMIA:002500-9796: Online Mendelian Inheritance in Animals (OMIA) [dataset].


2021 Castaneda, C., Ruiz, A.J., Tibary, A., Raudsepp, T. :
Molecular Cytogenetic and Y Copy Number Analysis of a Reciprocal ECAY-ECA13 Translocation in a Stallion with Complete Meiotic Arrest. Genes (Basel) 12:1892, 2021. Pubmed reference: 34946841. DOI: 10.3390/genes12121892.

Edit History

  • Created by Imke Tammen2 on 12 Jan 2022
  • Changed by Imke Tammen2 on 12 Jan 2022