Final answer:
DNA mutations within coding regions are known as synonymous or non-synonymous. Synonymous mutations do not change the amino acid sequence of a protein. Non-synonymous mutations involve changes that produce a different amino acid, possibly affecting protein function.
Step-by-step explanation:
DNA mutations within coding regions are either synonymous or non-synonymous. A synonymous mutation, also known as a silent mutation, occurs when a change in the DNA sequence does not result in a change to the amino acid sequence of a protein. This type of mutation is often considered neutral as it does not affect the protein's function. A synonymous mutation might occur due to the redundancy in the genetic code where multiple codons can encode for the same amino acid.
A non-synonymous mutation, on the other hand, involves a change in the DNA sequence that leads to a different amino acid being incorporated into the protein. This can have varying effects depending on the specific change. Missense mutations replace one amino acid with another, which might or might not affect the protein's function, depending on the chemical properties of the amino acids involved. For example, sickle cell disease is caused by a missense mutation. A nonsense mutation introduces a premature stop codon, often leading to a truncated and nonfunctional protein. Frameshift mutations, caused by insertions or deletions that are not in multiples of three, can result in an entirely different sequence of amino acids and typically result in nonfunctional proteins.