If your European ancestors survived the Bubonic Plague 700 years ago, they very likely may have also passed on to you a mutation of the CCR5 gene -- called delta 32. This may not sound exciting, but delta 32 is a powerful mistake. HIV, the virus that causes AIDS, attacks the human immune system, infecting the white blood cells sent to destroy it. The delta 32 mutation, however, effectively blocks the crucial gateway into human cells the virus needs. In fact, possessing delta 32 could save your life, and the lives of your children.
Gene Stories. "If your parents kept on having children, they’d have to visit the maternity hospital another million billion times to stand a chance of producing another child with your genes" (unless you're an identical twin of course).