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Telomeres are a class of repetitive DNA sequences that are located at chromosome termini and that act to stabilize the chromosome ends. The rapid karyotypic evolution of the genus Equus has given rise to ten taxa, all with different diploid chromosome numbers. Using fluorescence in situ hybridization (FISH) we localized the mammalian telomere sequence, (TTAGGG)(n), to the chromosomes of nine equid taxa. TTAGGG signal was located at chromosome termini in all species, however additional signal was seen at interstitial sites on some chromosomes in the Burchell's zebra, Equus quagga burchelli, the Hartmann's zebra, Equus zebra hartmannae, and at large heterochromatin-associated regions on the chromosomes of the donkey, Equus asinus. The interstitial signal in the zebras may be a relic of an ancient telomere-telomere fusion and mark the point at which two ancestral chromosomes may have fused. For the donkey, the heterochromatin-associated signal may represent degenerate telomere-like satellite sequences and identify a second type of satellite DNA for this taxon., (Copyright 2001 S. Karger AG, Basel)

A female bonobo (Pan paniscus) born at the San Diego Zoo exhibited inability to nurse and progressive weakness plus multiple congenital abnormalities including aural canal atresia and stenosis, malformed auricles, clenched hands, lordosis, agenesis of the caudal vertebra and cardiac abnormalities. Chromosome analysis identified the bonobo as being trisomic for chromosome 17, the homolog of human chromosome 18. Genotyping with human microsatellites suggested the extra chromosome was maternal in origin. In addition, a male lowland gorilla (Gorilla gorilla gorilla), also born at the zoo, exhibited postnatal growth retardation, facial dysmorphisms and small hands with short fingers. Karyotype analysis revealed the gorilla carried a deletion of the distal q arm of chromosome 3, the homolog of human chromosome 4. The phenotypic and karyotypic abnormalities found in the bonobo and gorilla were consistent with the characteristics of human trisomy 18 and human deletion 4q syndrome, respectively., (Copyright 2002 S. Karger AG, Basel)

Baboon (Papio hamadryas) metaphase chromosomes were analyzed using spectral karyotyping (SKY), a technique combining fluorescence microscopy, CCD-imaging, and Fourier spectroscopy. Results from a comparison of SKY analyses using probes derived from human chromosomes on baboon metaphases were consistent with the majority of comparative gene mapping data between the two species. These data were also compatible with earlier studies comparing macaque and human chromosomes. Human (HSA) chromosome 2 was homologous to baboon (PHA) chromosomes 12 (HSA 2q) and 13 (HSA 2p), whereas three baboon chromosomes corresponded to two different human chromosomes: PHA 3 to HSA 7 and HSA 21, PHA 7 to HSA 14 and HSA 15, and PHA 10 to HSA 20 and HSA 22. These results support the retained synteny between the Hominidae and Cercopithecidae genomes.

Giemsa-11 (G-11) staining and in situ hybridization were used to identify the equine chromosome complement of horse x mouse somatic cell hybrids. The presence of horse chromosomes in somatic cell hybrids was determined by differential G-11 staining. The slides were then destained and hybridized with biotinylated total horse (Equus caballus) genomic DNA without suppression. Fluorescence detection permitted rapid confirmation of horse chromosomal DNA in the hybrid cells.