People who cannot become infected with HIV have
A)extra T cells.
B)deletions in the genes encoding the CCR5 coreceptors.
C)a gene encoding a protein that attacks the virus.
D)anti-HIV antigens.

Question

Quizplus · Accepted Answer

Individuals with deletions in the CCR5 gene, which encodes a coreceptor used by HIV to enter CD4+ T cells, are resistant to HIV infection. Therefore, option B is the correct answer. Extra T cells (option A) and anti-HIV antigens (option D) are not known to confer complete resistance to HIV infection. While a few individuals possess a gene that produces a protein that inhibits HIV replication (option C), such cases are exceedingly rare.

People Who Cannot Become Infected with HIV Have