Origins of Hutu, Tutsi and Twa of neighboring people, it was almost non-existent among Rwandan Tutsi. Presence of the sickle cell trait is evidence of survival in the presence of malaria over many centuries, suggesting differing origins. Regional studies of the ability to digest lactose are also supportive. The ability to digest lactose among adults is widespread only among desert-dwelling nomadic groups that have depended upon milk for millennia. Three quarters of the adult Tutsi of Rwanda and Burundi have a high ability to digest lactose, while only 5% of the adults of the neighboring Shi people of eastern Congo can. Among Hutu, one in three
Rwandan genocide government blocked "Inyenyeri News", "The Rwandan", and "Le Prophete." In a documentary, BBC mentioned that a significant number of Hutus were killed and discussed theories of the RPF shooting down the president's plane. In response to the documentary, the Rwandan government shut down BBC in the local to BBC promoting a "revisionist" position on the genocide in a documentary. While before the genocide, Rwandan history textbooks would acknowledge and highlight differences between Tutsi and Hutu people, today, the only government approved Rwandan history textbook stresses the Rwandans as one people and virtually ignore the ethnic differences and pre-genocide conflicts. Furthermore,