Weapons designed to infect and then kill or sterilize specific ethnic groups are now possible, although none are yet thought to exist. Such genetic weapons would exploit naturally occurring differences in vulnerability among specific population groups. The potential to "target anatomical or physiological systems, including vision, or which use knowledge of human genetic similarities and differences to target weapons" are considerable. The potential effects of genetic weapons could be more insidious and less obvious than anything which exists presently. For example, it could be possible to design an agent to create sterility or pass on a lethal hereditary defect.
During the Vietnam War, an elite group of scientists working for the Pentagon was employed to carry out blood tests on select groups of Asians in order to 'prepare a map portraying the geographic distribution of human blood groups and other inherited blood characters'. The USA Department of Defence has been involved in research on Coccidioides immitis, commonly known as Valley Fever. The disease can result in a mortality rate of 50-60%, but only 1-11% of whites will develop the fatal form while 20-59% of blacks will do so. The SADF may currently be researching viruses, chemicals, and diseases which will affect only blacks.