Gene-ius

Comment:
For mutations, does a missense mutation *always* result in a changed amino acid- which may or may not result in a defective protein?
And a synonymous mutation does not result in a different amino acid?
Are both of these considered examples of “point” mutations?
Response:
A missense mutation, by definition, results in an amino acid change.  Depending on what the amino acid change is (conservative vs nonconservative) and it’s location in the protein, it may have no effect on the protein function.  The students don’t need to know this.  They just need to identify any mutation resulting with any amino acid change as a missense mutation. For the purposes of this event, a synonymous mutation is a change in a nucleotide which results in the same amino acid being used.  These are sometimes called “silent mutations” but a synonymous mutation may not actually be “silent” as it may still affect gene regulation, splicing etc. Again, the students don’t need to know that. Missense, synonymous and nonsense mutations are all point mutations but I will not use the term point mutation in the event and would not accept the answer of point mutation. They would be expected to identify it as one of the three.