A genetic mutation known as CCR5-delta 32 is responsible for the two types of HIV resistance that exist. CCR5-delta 32 hampers HIV's ability to infiltrate immune cells. The mutation causes the CCR5 co-receptor on the outside of cells to develop smaller than usual and no longer sit outside of the cell. CCR5 co-receptor is like door that allows HIV entrance into the cell. The CCR5-delta 32 mutation in a sense locks "the door" which prevents HIV from entering into the cell. 1% of people descended from Northern Europeans, particularly Swedes, are immune to HIV infection. These lucky people are homozygous carriers of the mutated gene - meaning that they inherited a copy from both of their parents. Another 10 -15% (the number has even suggested to be18%) of people with European heritage inherited one copy of the gene. Just one copy of the mutation does not prevent against infection. It does however reduce carrier's chances of infection and delays the progress of AIDS. Since the CCR5-delta 32 is tied primarily to the Eurasia region, the mutation has not been found in Africans, East Asians, or Amerindians.
Why does the CCR5-delta 32 mutation appear in people of European descent only? There is no solid answer to this question yet but many theories have been suggested. Along this line of reasoning scientists have suggested that past epidemics were the driving force behind the prevalence of the mutation in Europeans. CCR5-32 Delta is exciting. It presents possibilities for new ways to protect against HIV. Many wonder if genetic testing is available yet to see if one has the mutation. Understanding how and why certain people are resistant to HIV/AIDS with the help of CCR5-32 Delta will hopefully lead to new and highly successful treatments in our lifetime. [Source: www.nature.com]