Origins of Hutu, Tutsi and Twa adults has a high capacity for lactose digestion, a surprisingly high number for an agrarian people, which Mamdani suggests may be the result of centuries of intermarriage with Tutsi. Bethwell Ogot in the 1988 UNESCO "General History" further notes that the number of pastoralists in Rwanda increased sharply around the fifteenth century. Although Luis et al. (2004) in a more general study on bi-allelic markers in many African countries found a statistically significant genetic difference between Tutsi and Hutu, the overall difference were not large. Modern-day genetic studies of the Y-chromosome generally indicate that the Tutsi, like the Hutu, are
Genocides in central Africa Ituri conflict and the mass murder of Pygmies known as "Effacer le tableau". In Uganda, 300 thousand people were murdered during the regime of Idi Amin and 500 thousand during the rule of his successor, Milton Obote. Amin's genocides targeted the Acholi and Lango peoples; these two groups went on to murder other groups (mainly the Baganda) under Obote's regime. In the early 1970s, over 150 thousand Hutu people were killed by Tutsi people in Burundi by order of General Michel Micombero. Twenty years later, one million Tutsi people were murdered by Hutu people during the 1994 Rwandan genocide. In