Final answer:
The CCR5-delta 32 mutation originated a few thousand years ago, with its timing still debated, but is thought to have conferred resistance to past pandemics and spread through the Northern European population.
Step-by-step explanation:
The origin of the CCR5-delta 32 mutation, which confers resistance to HIV, is a topic of considerable debate within the scientific community. While the mutation is observed in modern populations and is beneficial against HIV, the link to historical diseases like plague is contested.
Estimates of the age of this mutation range from about 1875 to 225 years ago. The delta 32 CCR5 mutation likely originated in the Northern European population and may have been distributed farther through historical movements such as Viking invasions.
When considering the decay and linkage disequilibrium calculator, the mutation's origin is placed within a timeframe that might not seem long on a geological scale but represents a significant span in human history.
The degeneracy of the genetic code is an advantage in this context as it protects against negative impacts from mutations on natural selection and evolution by allowing certain mutations to have no effect on the protein function.