The sequence of DNA that is called a gene codes for a protein using DNA's four letter code. Three bases will code for one of twenty amino acids. When a gene is expressed, messenger RNA is transcribed from the DNA template and translated into a protein in the cytoplasm. If a single base in the sequence is missing, this mutation could

If a single base in the sequence is missing, this mutation could affect and disturb the whole frame-shift of protein synthesis

Explanation:

A single base missing or deletion will result in DNA mutation and will cause changes in the translated protein which will alter the function of the protein and sometimes the translated protein product is non functional.