 At least one "NBPF" gene has been found in Laurasiatherians, Euarchontoglires and elephants (but not other Afrotherians), but not in Xenarthrans (containing sloths).It was also found that several rodents, bats and eulipotyphla (containing hedgehogs) had lost the gene.It was found in 2012 that the exceptional increase in human Olduvai copy number was a result of multiple duplications within the "NBPF" genes primarily involving a sequential series of three variants of the domain.