What type of mutation is represented by the following sequence?
Original: 123456
Mutated: 154326
A.
Breakage
B.
Deletion
C.
Insertion
D.
Inversion
The Correct Answer and Explanation is :
The mutation represented by the sequence:
Original: 123456
Mutated: 154326
is an inversion (Option D).
Explanation:
Mutations are changes in the nucleotide sequence of the genome of an organism. They can occur in various forms, including deletions, insertions, inversions, and breakages. To identify the type of mutation in the given sequences, let’s analyze the changes between the original and mutated sequences:
- Original Sequence: 123456
- Mutated Sequence: 154326
In this case, the positions of the digits in the original sequence are rearranged in the mutated sequence. Specifically, the mutation involves:
- The original position 1 is now at position 5.
- The original position 2 is now at position 1.
- The original position 3 is now at position 4.
- The original position 4 is now at position 3.
- The original position 5 is now at position 2.
- The original position 6 is now at position 6 (it remains in the same position).
This rearrangement of the sequence is indicative of an inversion. Inversions occur when a segment of a chromosome is reversed end to end. In this case, segments of the sequence have been reversed, which aligns with the definition of an inversion mutation.
Types of Mutations:
- Breakage: Typically refers to the physical breaking of a chromosome, which is not directly applicable to the change observed here.
- Deletion: Involves the loss of a nucleotide sequence. There is no evidence of any nucleotides being lost in this case.
- Insertion: Involves the addition of extra nucleotides. There is no additional sequence present here.
- Inversion: Refers to the reversal of a segment of the chromosome. This is the most accurate description of the mutation in the given sequence.
Therefore, the correct answer is D. Inversion, as it best describes the rearrangement of the sequence observed.