Significance of the Missing Base Pairs
The frameshift mutation in Δ32 changes all amino acids after the deletion and introduces an early stop codon. Proteins this abnormal are degraded by the cell. Surprisingly, the lack of CCR5 doesn’t adversely affect people who are EU, so it’s not obvious who has relative protection against HIV. So far, we know two people with the Δ32 allele. But, how common is it?

The mutation in the EU men was detected by the time-consuming process of sequencing their CCR5 genes. Using this method to measure the frequency of the allele in the population is impractical, so a faster test was devised.

INSTRUCTIONS:
Click NEXT to see a genetic test for the CCR5 allele.