Adding an extra nucleotide to a dna sequence produces what type of mutation

Insertion

Explanation:

A mutation is any alteration to the nucleotide sequence of a DNA. It can result during its replication or be induced by mutation-causing components called Mutagens. When mutation involves a single nucleotide, it is referred to as POINT MUTATION.

Point mutation can occur either when a single nucleotide of a DNA molecule is removed/deleted, when it is replaced/substituted by another nucleotide, or when an additional nucleotide is included to the original sequence.

The last scenario of point mutation above is called INSERTION, the addition of a nucleotide disrupts the manner in which the sequence is read and can subsequently lead to the production of another polypeptide.

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