Germline

In biology and genetics, the germline of a mature or developing individual is the line (sequence) of germ cells that have genetic material that may be passed to a child.

For example, sex cells such as the sperm or the egg, are part of the germline. So are the cells that produce sex cells, called gametocytes, the cells that produce those, called gametogonia, and all the way back to the zygote, the cell from which the individual developed.

Cells that are not in the germline are called somatic cells. For example, all cells of the mammalian liver are somatic. If there is a mutation or other genetic change in the germline, it can be passed to offspring, but a change in a somatic cell will not be.

Germline cells are immortal, in the sense that they can reproduce indefinitely. This is enabled by a special enzyme called telomerase. This enzyme is dedicated to lengthening the DNA primer of the chromosome, allowing for unending duplication. Somatic cells, by comparison, can only divide around 30-50 times, as they do not contain telomerases.

"Germline" can refer to a lineage of cells spanning many generations of individuals; for example, the germline that links any living individual to the hypothetical first eukaryote of about one billion years ago, from which all plants and animals descend.

See also

* August Weismann
* Epigenetics
* Weismann barrier
* Germ line development


Wikimedia Foundation. 2010.

Look at other dictionaries:

  • germline — germ·line (jərmґlīn) the sequence of cells in the line of direct descent from zygote to gamete, as opposed to somatic cells (all other body cells). Mutations in germline cells are transmitted to progeny; those in somatic cells are not.… …   Medical dictionary

  • germline — noun those cells of an individual that have genetic material that could be passed to offspring; the source of gametes …   Wiktionary

  • Germline Mosaicism — Germline mosaicism, also known as gonadal mosaicism, is a condition in which the precursor (germline) cells to ova and spermatazoa are a mixture of two or more genetically different cell lines.External Link… …   Wikipedia

  • Germline mutation — A germline mutation is any detectable and heritable variation in the lineage of germ cells. Mutations in these cells are transmitted to offspring, while, on the other hand, those in somatic cells are not. A germline mutation gives rise to a… …   Wikipedia

  • Germline mutation — A heritable change in the DNA that occurred in a germ cell (a cell destined to become an egg or in the sperm) or the zygote (the conceptus) at the single cell stage. When transmitted to a child, a germline mutation is incorporated in every cell… …   Medical dictionary

  • germline mutation — A gene change in the body s reproductive cells (egg or sperm) that becomes incorporated into the DNA of every cell in the body of offspring; germline mutations are passed on from parents to offspring. Also called hereditary mutation …   English dictionary of cancer terms

  • germline insertion — /jerrm luyn /, Biotech. the insertion of cloned genes into the egg or sperm cell of an organism, using a gene transfer technique, in order to perpetuate a desired trait in its descendants, as pest resistance in a crop plant. * * * …   Universalium

  • germline insertion — /jerrm luyn /, Biotech. the insertion of cloned genes into the egg or sperm cell of an organism, using a gene transfer technique, in order to perpetuate a desired trait in its descendants, as pest resistance in a crop plant …   Useful english dictionary

  • Mutation, germline — A heritable change in the DNA that occurred in a germ cell (a cell destined to become an egg or in the sperm) or the zygote (the conceptus) at the single cell stage. When transmitted to a child, a germline mutation is incorporated in every cell… …   Medical dictionary

  • recombinational germline theory — a theory of the origin of antibody diversity, according to which the DNA coding for a single immunoglobulin chain is assembled by a somatic recombinational event from two genes, one a unique constant region gene and the other one of several… …   Medical dictionary


Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”

We are using cookies for the best presentation of our site. Continuing to use this site, you agree with this.