Figure 4.

Initiation of consanguineous marriages. In family with α⁺-thalassemia, shortage of marriageable candidates leads to cousin-cousin and "cousin"-outsider unions. With the likely distribution of α⁺-thalassemia alleles shown above, on an average, 20% more children in this consanguineous union will survive malaria than from a non-consanguineous union. Here, the excess deaths due to inbreeding = 0.7F, i.e., 4.4% [13].