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
Hutu Power Front (RPF) invasion, Habyarimana turned to inflaming ethnic tensions. Hutu Power acquired a variety of spokesmen. Hassan Ngeze, an entrepreneur recruited by the government to combat the Tutsi publication "Kanguka", created and edited "Kangura", a radical Hutu Power newsletter. He published the "Hutu Ten Commandments", which included the following: "Radio Télévision Libre des Mille Collines" broadcast radio shows suggesting the end to toleration of the Tutsi, repeating the Hutu Ten Commandments, and building support for the Hutu Power ideology. Two main voices of RTLM were announcers Valérie Bemeriki and Georges Ruggiu. The repetition of Hutu Ten Commandments was an attempt