Presence or absence of the NANOGNB gene in mammalian genomes. (A) The deduced homeodomain sequence of human NANOGNB showing predicted alpha helical regions, compatible with folding into a homeodomain tertiary structure. (B) NANOGNB is located just 15 kb from the human NANOG gene at chromosome 12p13.31 (orange arrows). Orthologous genes at the syntenic position are present in horse and dog, but not in mouse and rat. Grey arrows indicate non-homeobox genes.