A scan of Sam's genome for the 100 most common mutations known to cause RP didn't find anything. How can you explain this result?

He is either not carrying the gene for RP or the RP gene has mutated.

Explanation:

RP or Retina Pigmentosa is an eye defect inherited by a person from a parent. The disease is degenerative as the individual gradually loses his sight. It normally starts off as night-blindness and could go as bad as a total loss of sight.

The mutation of both the RPGR and RP2 genes which are responsible for the function and structure of light-reception in the eye accounts for most cases of Retina Pigmentosa disease.

i think the miocene epoch spans the time from 23 million to 12 million years ago.

1. efficient use of space

2. elimination of groundwater contamination

3. energy generation

4. lower carbon footprint