Concept explainers
Consider the phylogenetic tree below with three related species (A, B, C) that share a common ancestor (last common ancestor, or LCA). The lineage leading to species A diverges before the divergence of species B and C.
For gene X, no gene duplications have occurred in any lineage, and each gene X is derived from the ancestral gene X via
For gene Y, a gene duplication occurred in the lineage leading to A after it diverged from that leading to B and C. Are genes
For gene Z, gene duplications have occurred in all species. Define orthology and paralogy relationships for the different Z genes.
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Genetic Analysis: An Integrated Approach (3rd Edition)
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