The Multiple Genome Viewer (MGV) now includes 2 Xenopus genomes: the African clawed frog, X. laevis, and the the Western clawed frog, X. tropicalis. X. laevis is an allotetraploid (2n = 36) of hybrid origin. The resulting X. laevis genome has a set of ancestral ‘long’ (L) and ‘short’ (S) chromosomes, with extensive L/S homoeology for genes that have been retained on the S subgenome. The X. laevis.L and X. laevis.S subgenomes are represented as separate Genomes in the MGV.
For X. laevis, the Viewer can’t draw direct orthology links between L and S genome features because the Alliance does not create intraspecific orthology associations. If you turn on the inferred paralogs view in the Viewer, however, the “homoeology” links between corresponding L and S features are shown.