The proportions of various human Y-DNA haplogroups vary significantly from one ethnic or language group to another in Africa. Data in the table below are based on genetic research. Each group sampled is identified in the second column by linguistic designation: AA = Afroasiatic, KS = Khoisan, NS = Nilo-Saharan and NC = Niger–Congo. The third column gives the total sample size studied, and the other columns indicate the percentage observed of particular haplogroups.