1.5 Genetic Mutations and Inheritance

From Gametes to Zygote

Types of Mutations-Gene Mutation

In biology, we define mutation as a permanent change in an organism's DNA. Mutations are sometimes inherited by offspring. In this lesson, you will explore mutation that occurs at the gene level and at the chromosome level of DNA organization.

A gene mutation is a change in the normal base sequence of a gene. Gene mutations involve one or more base changes in a single gene, and take place when chromosomes duplicate during interphase. There are three types of gene mutations. A nucleotide base might be:

  • deleted

  • added

  • substituted

In each case, the mutation changes an organism's genetic code, and these changes can be passed to offspring.