<em>The type of mutation that occurred would be base pair deletion.</em>
Base pair deletion mutation is a type of mutation involving the deletion of one or more nucleotide bases from a DNA/gene. This causes a reduction in the base pairs and shortens the length of the DNA/gene
<u>For example, if the first codon of a gene with base sequence 'AGGGCTACG' is deleted, the gene becomes shortened with a new base sequence of 'GCTACG'. Thus, the mutated gene would have a shorter base pair when compared to its wild-type counterpart.</u>