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
Islam in Rwanda the Rwandan Genocide of 1994, Muslims were held in low regard, because they were seen as traders, in a land where farmers are highly regarded. The Muslim population before the genocide was 4% which was unusually low compared to that of neighbouring countries. Muslims were also affected by the genocide. There were only a few incidents in which Tutsis in mosques were attacked. The most widely known example occurred at Nyamirambo Main Mosque, where hundreds of Tutsi had gathered to take refuge. The refugees in the mosque fought off Hutu militias with stones, bows and arrows, putting up stiff resistance