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A selective sweep in chimpanzees

4 important questions on A selective sweep in chimpanzees

What is the difference between the binding of MHC class I and class II?

MHC I get intracellular infections (binds molecules tighter and therefore harder to bind) and MHC II are extracellular infections (binds easier to molecules due to more outside binding) --> thus different repertoires

How can chimpanzees still get AIDS when they don't seem to have an immune response?

A specific recombinant or combination of variants can lead to AIDS, but mostly die at age --> probably have a longer history with HIV and can clean up the virus quickly

Why are chimpanzees relatively resistant to AIDS?

Candidate resistance genes --> MHC class I --> humans didn’t show AL gene compared to chimps, however, did not make the difference, thus is in the details

- Chimpanzees experienced a selective sweep affecting the MHC class I gene repertoire, approximately 2-3 myr, as was illustrated by intron 2 analysis
- Chimpanzees only have MICB and not MICA that humans do have  are the best lead for fighting the HIV infection  displaying limited polymorphism
Hypothesis: The MHC class I repertoire reduction in chimpanzees may have been caused by an HIV-1/SIV like retrovirus

What was the conclusion of the study in which they investigated whether the selective sweep was possibly caused by HIV-1/SIV and has resulted in the preferential selection of Patr class I molecules that are like AIDS-resistant molecules in human individuals, such as HLA-B27/B57? What is a selective sweep?

The chimpanzee MHC class I repertoire is skewed to favour the survival of animals whose Patr molecules recognize conserved areas of Gag, a property shared with HLA-B*27/B*57.

Selective sweep: recombination of genes that give different phenotypes  but selected on a specific characteristic

The question on the page originate from the summary of the following study material:

Immunobiology

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