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
Sainte-Famille Church genocide of 1994 thousands of Tutsi and Hutu took refuge in the church and many were massacred, following the death of President Juvénal Habyarimana. Witnesses said that the priest in charge of the church, Father Wenceslas Munyeshyaka, armed himself and helped Hutu militias take people from the church to be killed. Munyeshyaka was responsible for many of the killings, agreeing to "let the militia pick off those they wanted every now and then." Wenceslas Munyeshyaka hated the Tutsis and called them the "inyenzis". Following this incident and similar ones in other churches, many of the Rwandan people converted to Islam.