Here is a name and address
Joseph Smith
1234 3rd Street
Mesa, CA
We have information that we can go to his house and meet him
Let’s add a letter by mutation. (we have added information)
Joseph Smithy
We can go to his house but we will not meet Joseph Smithy.
Here we see a mutation that results in an inability to meet Joseph Smithy.
Mutations result in loss of function or ability. They limit or lose a prior expression.
If we add a number to the address the same thing will happen. We go to the house number 12345 but no one named Joseph Smith is there.