 In Altheide and Hammer 1997, the authors argue that haplogroup E arose in Asia on an ancestral YAP+ allele before migrating back to Africa.However some studies, such as Semino et al., indicate that the highest frequency and diversity of haplogroup E is in Africa, and East Africa is the most likely place of origin of the haplogroup.The models supporting an African origin or an Asian origin of the YAP+ insertion both required the extinction of the ancestral YAP chromosome to explain the current distribution of the YAP+ polymorphism.