What are insertions and deletions?
Insertions and deletions are types of DNA mutations. They are places in your DNA where extra nucleotides, cytosine (C), guanine (G), Adenine (A), and Thymine (T), have been added or part of the sequence has been deleted. Insertions are where an extra nucleotide has been added to a sequence during the copy process. A common example of an insertion is 309.1C in the second hypervariable region, HVR2. If you have an insertion after base pair 309, for example, the insertion will be listed as the base pair and .1C. In this case, a single base pair insertion has been found in your mtDNA string, noted by the .1. The nucleotide added is cytosine (C), therefore denoted with a C. The insertion then looks like this: 309.1C. If you have a two base pair insertion the results might look like this: 309.1C, 309.2C. A deletion is where a nucleotide has not been copied. The sequence will not have result for that place. When a deletion is found in a sequence it is represented with a minus sign. For exampl
In some cases you will see insertions in your mtDNA sequence. If you have an insertion after base pair 255, for example, the insertion will be listed as the base pair and .1C. In this case, a single base pair insertion has been found in your mtDNA string, noted by the .1. The nucleotide changed to cytosine (C) from guanine (G), therefore denoted with a C. The insertion then looks like this: 255.1C. If you have a 2 base pair insertion the results might look like this: 255.1C 255.2A. It is also possible that you have a deletion; a base pair was not copied and you just don’t have a base pair at that particular place in your sequence. For example, “522 -” means that this location, 522, isn’t in your sequence and is represented by a minus sign at the site where the nucleotide base should have been found.
