Africa. A 2000 study concerning the origin of the YAP+ mutation analyzed 841 Y-chromosomes representing 36 human populations of wide geographical distribution for the presence of a Y-specific Alu insert (YAP+ chromosomes). They also analyzed the Out-of-Africa and out-of-Asia models for the YAP mutations. According to the authors, the most ancient YAP+ mutation was found in the Asian lineage of Tibetans, but curiously not in Japanese lineages. More recent YAP+ lineages were distributed almost equally in Asians and Africans, with a smaller distribution in Europe. The scientists concluded that the information available did not allow one to decide between the out-of-Asia or out-of-Africa models. They further suggested that the YAP+ mutation had already originated 141,000 years ago. Contemporary studies Since 2000, a number of scientists began to reassess the hypothesis of an Asian origin of the YAP insertion and to suggest an African origin. Underhill et al. 2001 identified the D-M174 mutation that defines haplogroup D. The M174 allele is found in the ancestral state in all African lineages including haplogroup E. The discovery of M174 mutation meant that haplogroup E could not be a subclade of haplogroup D. These findings effectively neutralized the argument of an Asian origin of the YAP+ based on the character state of the M40 and M96 mutations that define haplogroup E. According to Underhill et al. 2001, the M174 data alone would support an African origin of the YAP insertion. 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. Paragroup DE* possesses neither the mutations that define haplogroup D or haplogroup E. If paragroup DE* was found in one location but not the other, it would boost one theory over the other. Haplogroup DE* has been found in Nigeria, Guinea-Bissau and also in Tibet. The phylogenetic relationship of three DE* sequences has yet to be determined, but it is known that the Guinea Bissau sequences differ from the Nigerian sequences by at least