Evolutionary scenario proposing the potential role of whole genome duplications in AANAT diversification.

<p>Whole genome duplications are indicated by a red arrow: they concern vertebrates (2R), teleosts (3R) and salmonids (4R). Some <i>aanat</i> duplications were followed by secondary losses and are represented by shaded cells in the table or dotted branches on the tree. Other <i>aanat</i> paralogs diverged to form various isoforms as shown in different colors when present in a given phylum. The exact timing of the <i>aanat1</i>/<i>2</i> duplication cannot be inferred from current genomic data and ranges between the 2R and the Actinopterygii/Sarcopterygii split.