Abstract
The past decade has witnessed an explosion of genome sequencing and mapping in evolutionary diverse species. While full genome sequencing of mammals is rapidly progressing, the ability to assemble and align orthologous whole chromosome regions from more than a few species is still not possible. The intense focus on building of comparative maps for companion (dog and cat), laboratory (mice and rat) and agricultural (cattle, pig, and horse) animals has traditionally been used as a means to understand the underlying basis of disease-related or economically important phenotypes. However, these maps also provide an unprecedented opportunity to use multispecies analysis as a tool for inferring karyotype evolution. Comparative chromosome painting and related techniques are now considered to be the most powerful approaches in comparative genome studies. Homologies can be identified with high accuracy using molecularly defined DNA probes for fluorescence in situ hybridization (FISH) on chromosomes of different species. Chromosome painting data are now available for members of nearly all mammalian orders. In most orders, there are species with rates of chromosome evolution that can be considered as 'default' rates. The number of rearrangements that have become fixed in evolutionary history seems comparatively low, bearing in mind the 180 million years of the mammalian radiation. Comparative chromosome maps record the history of karyotype changes that have occurred during evolution. The aim of this review is to provide an overview of these recent advances in our endeavor to decipher the karyotype evolution of mammals by integrating the published results together with some of our latest unpublished results.
Highlights
The past decade has witnessed an explosion of genome sequencing and mapping in evolutionary diverse species
Chiroptera, Pholidota, and Eulipotyphla), Xenarthra, and Afrotheria (Proboscidea, Sirenia, Hyracoidea, Afrosoricida, Tubulidentata, and Macroscelidea) [1]. This modern phylogenetic tree serves as a useful scaffold for combining the various parts of a puzzle in comparative mammalian cytogenetics
It is widely appreciated that species may have phenetically similar karyotypes because they are genomically conservative
Summary
The Postgenomic research in mammalian cytogenetics has confirmed the previously established general tendencies of karyotype evolution, brought new data for finalizing phylogenetic trees and allowed a detail analysis of genome evolution in various branches. Studies of mammalian genome evolution are set to take a quantum leap as ever more completely sequenced multiple genomes become available. The previously studied karyotypes characterized from techniques ranging from classical staining and banding to molecular cytogenetic approaches from chromosome paints to cloned DNA will serve as basis for high resolution maps construction for hundreds of mammalian and vertebrate species. A newly proposed Genome 10 K project presumes whole genome sequencing of 10,000 vertebrate species in the near future (G10KCOS 2009), which will provide a foundation for the generation of postgenomic studies
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
