Chromosome Rearrangement Patterns in Mammalian Evolution

Abstract

Closely related species often have the same or similar karyotypes. This has been demonstrated in classical genetics with salivary gland chromosomes of different Drosophila species, in which the sequence of rearrangements that occurred during evolution can often be traced. Recently, molecular cytogenetics has proved that this is also true for mammalian chromosomes. The inspection of chromosomal changes with molecular defined probes by fluorescence in situ hybridization (FISH) allows the interpretation of the single or multiple steps that changed genomes during evolution. Comparative chromosome painting or ‘Zoo‐FISH’ and related techniques are now considered as one of the most powerful approaches in comparative genome studies for the understanding of the mode and tempo of gross genomic changes in primates and other mammals. For many nodes in mammalian phylogeny landmark chromosome rearrangements have now been identified that would discriminate ancestral versus derived chromosome changes and help to elucidate species phylogenies.