The correct sequence is:
CAG GCG CGG TCT
This creates the following amino acids:
Glutamine - Alanine - Arginine - Leucine
The observed mistake on the sequence (highlighted):
CAG GAG CGG TCT
1. The name of the wrong amino acid:
Glutamic acid - GAG (replaces Alanine - GCG)
2. A mistake in the mRNA sequence, cause a mutation and the creation of a different protein. This eventually will form an incorrect protein, or even the not production of any protein at all, due to an incorrect indication by the aminoacidic chain. Multiple diseases or pathologies are caused by this, the body doesn't produce the correct protein, and a process like the expression of certain genes would be affected, expressing genes that are the cause of that conditions.