Germline mutation

A Germline Mutation is any detectable, heritable variation in the lineage of germ cells. Mutations in these cells are transmitted to offspring while those in somatic cells are not.

This distinction is most important in animals, where germ cells are distinct from somatic cells. However, in plants, the reproductive cells in a particular flower will be derived from the same meristem as the cells in that flower and on the stem leading to the flower, which is a different population of cells than those that give rise to the other flowers on the plant. Single-celled organisms have no distinction between germline and somatic tissues.

In animals, mutations are more likely to occur in sperm than in ova, because a larger number of cell divisions are involved in the production of sperm.
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