This domain has been characterized in the finding of a developmental pluripotency associated gene (Dppa) in the lower vertebrate Xenopus laevis [1]. Previous to this discovery, Dppa genes were known only in higher vertebrates. The domain is subject to structure determination by the Joint Center of Structural Genomics.

1: Functional dissection of XDppa2/4 structural domains in Xenopus development. Siegel D, Schuff M, Oswald F, Cao Y, Knochel W; Mech Dev. 2009;126:974-89. PMID:19772919