Population of a multicellular organism's cells that pass on their genetic material to the progeny
In biology and genetics, the germline is the population of a multicellular organism's cells that develop into germ cells. In other words, they are the cells that form gametes (eggs and sperm), which can come together to form a zygote. They differentiate in the gonads from primordial germ cells into gametogonia, which develop into gametocytes, which develop into the final gametes.[1] This process is known as gametogenesis.
Germ cells pass on genetic material through the process of sexual reproduction. This includes fertilization, recombination and meiosis. These processes help to increase genetic diversity in offspring.[2]
Certain organisms reproduce asexually via processes such as apomixis, parthenogenesis, autogamy, and cloning.[3][4] Apomixis and Parthenogenesis both refer to the development of an embryo without fertilization. The former typically occurs in plants seeds, while the latter tends to be seen in nematodes, as well as certain species of reptiles, birds, and fish.[5][6] Autogamy is a term used to describe self pollination in plants.[7] Cloning is a technique used to creation of genetically identical cells or organisms.[8]
In sexually reproducing organisms, cells that are not in the germline are called somatic cells. According to this definition, mutations, recombinations and other genetic changes in the germline may be passed to offspring, but changes in a somatic cell will not be.[9] This need not apply to somatically reproducing organisms, such as some Porifera[10] and many plants. For example, many varieties of citrus,[11] plants in the Rosaceae and some in the Asteraceae, such as Taraxacum, produce seeds apomictically when somatic diploid cells displace the ovule or early embryo.[12]
In an earlier stage of genetic thinking, there was a clear distinction between germline and somatic cells. For example, August Weismann proposed and pointed out, a germline cell is immortal in the sense that it is part of a lineage that has reproduced indefinitely since the beginning of life and, barring accident, could continue doing so indefinitely.[13] However, it is now known in some detail that this distinction between somatic and germ cells is partly artificial and depends on particular circumstances and internal cellular mechanisms such as telomeres and controls such as the selective application of telomerase in germ cells, stem cells and the like.[14]
Not all multicellular organisms differentiate into somatic and germ lines,[15] but in the absence of specialised technical human intervention practically all but the simplest multicellular structures do so. In such organisms somatic cells tend to be practically totipotent, and for over a century sponge cells have been known to reassemble into new sponges after having been separated by forcing them through a sieve.[10]
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 last universal common ancestor, from which all plants and animals descend.
^Yao, C., Yao, R., Luo, H., & Shuai, L. (2022). Germline specification from pluripotent stem cells. Stem cell research & therapy, 13(1), 74. https://doi.org/10.1186/s13287-022-02750-1
^Zickler, D., & Kleckner, N. (2015). Recombination, Pairing, and Synapsis of Homologs during Meiosis. Cold Spring Harbor perspectives in biology, 7(6), a016626. https://doi.org/10.1101/cshperspect.a016626
^Tarín, Juan J.; Cano, Antonio, eds. (2000). Fertilization in protozoa and metazoan animals: cellular and molecular aspects. Berlin Heidelberg: Springer. ISBN 978-3-540-67093-3.
^Lowe, Andrew; Harris, Stephen; Ashton, Paul (1 April 2000). Ecological Genetics: Design, Analysis, and Application. John Wiley & Sons. ISBN 978-1-444-31121-1.
^Niccolò, T., Anderson, A. W., & Emidio, A. (2023). Apomixis: oh, what a tangled web we have!. Planta, 257(5), 92. https://doi.org/10.1007/s00425-023-04124-0
^Dudgeon, C. L., Coulton, L., Bone, R., Ovenden, J. R., & Thomas, S. (2017). Switch from sexual to parthenogenetic reproduction in a zebra shark. Scientific reports, 7, 40537. https://doi.org/10.1038/srep40537
^Eckert, Christopher G. (February 2000). "Contributions of Autogamy and Geitonogamy to Self-Fertilization in a Mass-Flowering, Clonal Plant". Ecology. 81 (2). Ecological Society of America: 532–542. doi:10.1890/0012-9658(2000)081[0532:COAAGT]2.0.CO;2. ISSN 0012-9658 – via John Wiley and Sons.
^Bonetti, G., Donato, K., Medori, M. C., Dhuli, K., Henehan, G., Brown, R., Sieving, P., Sykora, P., Marks, R., Falsini, B., Capodicasa, N., Miertus, S., Lorusso, L., Dondossola, D., Tartaglia, G. M., Cerkez Ergoren, M., Dundar, M., Michelini, S., Malacarne, D., Beccari, T., … Bertelli, M. (2023). Human Cloning: Biology, Ethics, and Social Implications. La Clinica terapeutica, 174(Suppl 2(6)), 230–235. https://doi.org/10.7417/CT.2023.2492
^C.Michael Hogan. 2010. Mutation. ed. E.Monosson and C.J.Cleveland. Encyclopedia of Earth. National Council for Science and the Environment. Washington DC Archived April 30, 2011, at the Wayback Machine
^ abBrusca, Richard C.; Brusca, Gary J. (1990). Invertebrates. Sunderland: Sinauer Associates. ISBN 978-0878930982.
^Akira Wakana and Shunpei Uemoto. Adventive Embryogenesis in Citrus (Rutaceae). II. Postfertilization Development. American Journal of Botany Vol. 75, No. 7 (Jul., 1988), pp. 1033-1047 Published by: Botanical Society of America Article Stable URL: https://www.jstor.org/stable/2443771
^K V Ed Peter (5 February 2009). Basics Of Horticulture. New India Publishing. pp. 9–. ISBN 978-81-89422-55-4.
^August Weismann (1892). Essays upon heredity and kindred biological problems. Clarendon press.
^Watt, F. M. and B. L. M. Hogan. 2000 Out of Eden: Stem Cells and Their Niches Science 287:1427-1430.
^Radzvilavicius, Arunas L.; Hadjivasiliou, Zena; Pomiankowski, Andrew; Lane, Nick (2016-12-20). "Selection for Mitochondrial Quality Drives Evolution of the Germline". PLOS Biology. 14 (12): e2000410. doi:10.1371/journal.pbio.2000410. ISSN 1545-7885. PMC 5172535. PMID 27997535.
In biology and genetics, the germline is the population of a multicellular organism's cells that develop into germ cells. In other words, they are the...
Germline mosaicism, also called gonadal mosaicism, is a type of genetic mosaicism where more than one set of genetic information is found specifically...
A germline mutation, or germinal mutation, is any detectable variation within germ cells (cells that, when fully developed, become sperm and ova). Mutations...
Human germline engineering is the process by which the genome of an individual is edited in such a way that the change is heritable. This is achieved by altering...
mutation in a parent. A germline mutation can be passed down through subsequent generations of organisms. The distinction between germline and somatic mutations...
primordial germ cells, migrate to the location of the gonad, and form the germline of the animal. Cleavage in most animals segregates cells containing germ...
into the cell or using gene-editing technology. This process is known as germline engineering and performing this on embryos that will be brought to term...
immunoglobulin diversity that proposed that each antibody was encoded in a separate germline gene. This does not occur in most species (including humans), but may occur...
and they only divide by mitosis. The lineage of germ cells is called the germline. Germ cell specification begins during cleavage in many animals or in the...
models explaining how restriction arose are the germline model and the selection model. The germline model suggests that MHC restriction is a result of...
that in somatic cells from the same individual. This low frequency in the germline leads to embryos that have a low frequency of point mutations in the next...
In contrast, gametes derive from meiosis within the germ cells of the germline and they fuse during sexual reproduction. Stem cells also can divide through...
occurs in a cell other than a gamete, germ cell, or gametocyte. Unlike germline mutations, which can be passed on to the descendants of an organism, somatic...
inheritance. In more precise terminology, hereditary information moves only from germline cells to somatic cells (that is, somatic mutations are not inherited)....
Agency (EMA) approved olaparib as monotherapy. The FDA approval is in germline BRCA mutated (gBRCAm) advanced ovarian cancer that has received three or...
the informational redundancy needed to repair damage in the DNA of the germline. The repair process used appears to involve homologous recombinational...
A micronucleus is a small nucleus that forms whenever a chromosome or a fragment of a chromosome is not incorporated into one of the daughter nuclei during...
Recently reported estimates of the human genome-wide mutation rate. The human germline mutation rate is approximately 0.5×10−9 per basepair per year....
skin onto 80 percent of the boy's body which was affected by the illness. Germline gene therapy would result in any change being inheritable, which has raised...
of cancer. Some germline mutations in DNA repair genes cause up to 100% lifetime chance of cancer (e.g., p53 mutations). These germline mutations are indicated...
miwi (for mouse piwi). PIWI proteins play a crucial role in fertility and germline development across animals and ciliates. Recently identified as a polar...
Drosophila melanogaster male and female germline development. This structure has roles in maintaining germline cysts, coordinating the number of mitotic...
cells (OSCs), also known as egg precursor cells or female germline cells, are diploid germline cells with stem cell characteristics: the ability to renew...
Rybarska A, Hoege C, Gharakhani J, Jülicher F, Hyman AA (June 2009). "Germline P granules are liquid droplets that localize by controlled dissolution/condensation"...
The RASopathies are a group of developmental syndromes caused by germline mutations in genes belonging to the Ras/MAPK pathway. Common features include...
Neonatal Physiology, p. 80 (Elsevier Health Sciences 2007). "Editing human germline cells sparks ethics debate". May 6, 2015. Archived from the original on...
but do not prohibit germline engineering. A 2020 issue of the journal Bioethics was devoted to moral issues surrounding germline genetic engineering in...