What term is used to describe the changes in gene sequence that have occurred?

A gene mutation is a permanent change to the base pair sequence (the building blocks of DNA) that makes up a gene. A mutation can affect one base pair, a larger segment, or even several genes.

While acquired mutations can occur at any point in an individual's life and are only found in a subset of body cells, inherited mutations are present in nearly every cell of the body and are inherited from a parent. Acquired mutations can be caused by environmental factors like UV radiation from the sun or mistakes a cell makes when copying its own DNA during cell division.

Different methods can modify the DNA sequence, and each mutation type can impact a cell's, tissue's, or person's health differently.

Types of gene mutations that could occur:

Deletion: the DNA contains one or more base pairs that are removed; a gene or several genes may also be eliminated.

Insertion is the addition of one or more base pairs to the DNA.

Gene duplication—which is actually a major evolutionary drive—is not the same as duplication, which is the mistaken copying of a single DNA strand, resulting in the elongation of the gene.

Repeat expansion is a process that is quite similar to duplication in that it occurs when a repetitive sequence in DNA is inadvertently copied more than once. This occurs when the cell's copy machine becomes confused by the repeats and becomes stuck on them for a while.

Three different types of mutations can occur in a gene: missense, nonsense, and frameshift mutations. These mutations can cause different outcomes depending on the specific amino acid that each of the three base pairs in the gene codes for.

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"Mutation" is the term used to describe changes in the sequence of genes.