 Myomegalin is a paralog (duplicated relative) of CDK5RAP2, a centrosomal protein involved in the cell cycle, of neurons especially, that lacks Olduvai sequences but, when mutated, has been implicated in microcephaly.Orthologs of myomegalin can be seen in vertebrates as far back as bony fish, around 450 million years ago, however, the Olduvai domain is not clearly seen until the emergence of mammals.The first Olduvai domain located outside of myomegalin is seen approximately 100–150 million years ago, when the domain was included in a duplication and transposition event which created a new gene, "NBPF1", which would eventually later give rise to a family of duplicated "NBPF" genes.