Accelerated evolution of 3'avian FOXE1 genes, and thyroid and feather specific expression of chicken FoxE1.

Background: The forkhead transcription factor gene E1 (FOXE1) plays an important role in regulation of thyroid development, palate formation and hair morphogenesis in mammals. However, avian FOXE1 genes have not been characterized and as such, codon evolution of FOXE1 orthologs in a broader evolutionary context of mammals and birds is not known.

Results: In this study we identified the avian FOXE1 gene in chicken, turkey and zebra finch, all of which consist of a single exon.