genetic distance analysis was carried out among seven tribes of the sudan comprising three negroid ( nuba , fur , and nilotes ) and four arab tribes ( beja , gaalin , hawazma , and messeria ) on the basis of six polymorphic loci ( abo and rhesus blood groups ; haemoglobin and red cell glucose-6-phosphate dehydrogenase ; serum haptoglobin and transferrin polymorphisms ) controlling 21 alleles and compared with the arab and negroid populations in neighbouring countries .
C0019046
haemoglobin
C0014792
red cell