Chromosome Complement: Differences between Equus caballus and Equus przewalskii, Poliakoff

@article{Benirschke1965ChromosomeCD,
  title={Chromosome Complement: Differences between Equus caballus and Equus przewalskii, Poliakoff},
  author={Kurt Benirschke and N. Malouf and Richard J. Low and Heinz Heck},
  journal={Science},
  year={1965},
  volume={148},
  pages={382 - 383}
}
The chromosome number of the domestic horse is 2n = 64; different races have the same complement. The chromosomes of two Przewalski's horses (at Catskill Game Farm, New York), presumably ancestral wild horses from Mongolia, are identical: 2n = 66, with more acrocentric and fewer metacentric elements than the chromosomes of the domestic horse. This apparent difference in karyotype may help resolve the questions of "purity" in the relatively few remaining Przewalski's horses. Moreover, these… 
Chromosome Complement: A Fertile Hybrid between Equus priewalskii and Equus caballus
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At the Zoological Garden of Antwerp it has been proved that when Equus prjewalskii is crossed with E. caballus the offspring is fertile and meiosis in the hybrid was successfully achieved.
Fixed nucleotide differences on the Y chromosome indicate clear divergence between Equus przewalskii and Equus caballus.
The phylogenetic relationship between Equus przewalskii and E. caballus is often a matter of debate. Although these taxa have different chromosome numbers, they do not form monophyletic clades in a
A centric fission and heterochromatin polymorphism in Equus asinus Spanish breeds
TLDR
All Spanish asinine specimens correspond to a single population, from the chromosomal point of view, and results show no polymorphisms which can be attributed to a particular breed.
Horse domestication and conservation genetics of Przewalski's horse inferred from sex chromosomal and autosomal sequences.
TLDR
X chromosomal and autosomal data do not place Przewalski's horses in a separate clade within phylogenetic trees for horses, suggesting a close relationship between domestic and Przine's horses and the hypothesis that very few male horses along with numerous female horses founded the various domestic horse breeds is supported.
Karyotypic relationships of horses and zebras: results of cross-species chromosome painting
TLDR
The comparative maps of equids allow for the unequivocal characterization of chromosomal rearrangements that differentiate the karyotypes of these equid species.
FISH analysis comparing genome organization in the domestic horse (Equus caballus) to that of the Mongolian wild horse (E. przewalskii)
TLDR
A comparative gene map between ECA and EPR by FISH mapping 46 domestic horse-derived BAC clones containing genes previously mapped to ECA chromosomes indicated that all ECAand EPR chromosomes were homologous as predicted by GTG banding, but provide new information in that the EPR acrocentric chromosomes EPR23 and E PR24 were shown to be homologues of the ECA metacentric chromosome ECA5.
Comparative Placentation
TLDR
The ancestry of horses from five-toed species via the small Eohippus of the American continent has been a prime topic of study for evolutionary biologists, causing karyotypes to evolve that range from 66 to 32 chromosomes, whilst preserving the same amount of DNA.
Mitochondrial control region and 12S rRNA variation in Przewalski's horse (Equus przewalskii).
TLDR
Variation in the control region and the 12S rRNA gene of all surviving mitochondrial lineages of Przewalski's horse was investigated butylogenetic comparison of these sequences, with sequences for the domestic horse, does not resolve the ancestral status of either horse.
Equus przewalskii (Mongolian wild horse)
One of the small acrocentrics shows frequently a pronounced secondary constriction of the long arm near the centromere, similar to that of the domestic horse. Delicate satellites occur on the short
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The financial support for these studies by the NIH (GM 10210) is gratefully acknowledged