Editing Comparative genomics (section)

=== Genome maps ===
An additional method in comparative genomics is [[genetic mapping]]. In genetic mapping, visualizing [[synteny]] is one way to see the preserved order of genes on chromosomes. It is usually used for chromosomes of related species, both of which result from a common ancestor.<ref>{{cite book | vauthors = Duran C, Edwards D, Batley J | title = Plant Genomics | chapter = Genetic Maps and the Use of Synteny | series = Methods in Molecular Biology | volume = 513 | pages = 41–55 | date = 2009 | pmid = 19347649 | doi = 10.1007/978-1-59745-427-8_3 | isbn = 978-1-58829-997-0 }}</ref> This and other methods can shed light on evolutionary history. A recent study used comparative genomics to reconstruct 16 ancestral [[karyotype]]s across the mammalian phylogeny. The computational reconstruction showed how chromosomes rearranged themselves during mammal evolution. It gave insight into conservation of select regions often associated with the control of developmental processes. In addition, it helped to provide an understanding of chromosome evolution and [[genetic diseases]] associated with DNA rearrangements.{{Citation needed|date=December 2022}}
[[File:Reconstruction of mammillian chromosomes.png|alt=Solid green squares indicate mammalian chromosomes maintained as a single synteny block (either as a single chromosome or fused with another MAM), with shades of the color indicating the fraction of the chromosome affected by intra-chromosomal rearrangements (the lightest shade is most affected). Split blocks demarcate mammalian chromosomes affected by inter-chromosomal rearrangements. Upper (green)triangles show the fraction of the chromosome affected by intra chromosomal rearrangements, and lower (red) triangles show the fraction affected by inter chromosomal rearrangements. Syntenic relationships of each MAM to the human genome are given at the right of the diagram. MAMX appears split in goat because its X chromosome is assembled as two separate fragments. BOR, boreoeutherian ancestor chromosome; EUA, Euarchontoglires ancestor chromo-some; EUC, Euarchonta ancestor chromosome; EUT, eutherian ancestor chromosome; PMT; Primatomorpha ancestor chromosome; PRT, primates (Hominidae) ancestor chromosome; THE, therian ancestor chromosome.|thumb|upright=1.5|Image from the study Evolution of the ancestral mammalian karyotype and syntenic regions. It is a Visualization of the evolutionary history of reconstructed mammalian chromosomes based on the human lineage.<ref name="Evolution of the ancestral mammalia"/>]]