What process occurs from a change in the structure of a gene? in order;

The correct order of processes that occur from a change in the structure of a gene is:

1. **A nucleotide base on the DNA strand is changed**
2. **DNA codes for a different amino acid sequence**
3. **A different protein may be produced**
4. **A different trait may be observed**

This sequence outlines how a mutation in the DNA can lead to changes at the protein level, which in turn can affect observable traits.