AAMC FL Practice Exam

Most DNA mutations are characterized by what structural feature?

1. Long sequences

2. Palindromic sequences

3. Base pair duplications

4. Translocations

The correct answer is: Palindromic sequences

The correct choice identifies that most DNA mutations are characterized by palindromic sequences. Palindromic sequences in DNA have the unique property of being able to read the same forward and backward on complementary strands, which plays a significant role in various biological processes, including DNA replication and repair. These sequences are particularly relevant in the context of certain types of mutations, such as those that arise during the activity of restriction enzymes, which recognize palindromic sites to cut DNA, or during the formation of hairpin loops in nucleic acids. While long sequences, base pair duplications, and translocations are all forms of mutations, they do not universally characterize the majority of DNA mutations. Long sequences are too vague to provide a specific structural feature, base pair duplications are a specific type of mutation that occurs less frequently than others, and translocations involve segments of DNA but do not encompass the broader spectrum of mutations experienced across the genome. Palindromic sequences, on the other hand, embody a distinctive and widespread characteristic of numerous mutations and their implications in genetic function.