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'''Structural inheritance''' is the transmission of a trait in a living [[organism]] by a self-perpetuating spatial structures. This is in contrast to the transmission of digital information such as is found in [[DNA]] sequences, which accounts for the vast majority of known [[genetics|genetic]] variation.
Examples of structural inheritance include the propagation of [[prion]]s, the infections agents of diseases such as scrapie (in sheep and goats), bovine spongiform encephalopathy ('mad cow disease') and Cruetzfeld-Jakob disease (although the protein-only hypothesis of prion transmission has been considered contentious until quite recently <ref> Soto C, Castilla J. The controversial protein-only hypothesis of prion propagation. Nat Med. 2004 Jul;10 Suppl:S63-7. <ref/>). Prion-like propagating secondary stuctures also exist in [[yeast]] <ref>Tuite MF, Lindquist SL. Maintenance and inheritance of yeast prions. Trends Genet. 1996 Nov;12(11):467-71.</ref> ,<ref>Serio TR, Cashikar AG, Kowal AS, Sawicki GJ, Lindquist SL. Self-perpetuating changes in Sup35 protein conformation as a mechanism of heredity in yeast. Biochem Soc Symp. 2001;(68):35-43.<ref/>. Structural inheritance has also been seen in the orientation of [[cilium|cilia in protozoans such as ''Paramecium''<ref> BEISSON, J. & SONNEBORN, T. M. (1965). Cytoplasmic inheritance of the organization of the cell cortex of Paramecium aurelia. Proc. natn. Acad Sci. U.S.A. 53, 275-282 </ref> and [http://dev.biologists.org/cgi/reprint/105/3/447| ''Tetrahymena''], and 'handedness' of the sprial of the cell in [http://dev.biologists.org/cgi/reprint/105/3/447| ''Tetrahymena''], and shells of snails. Some [[organelle]]s also have structural inheritance, such as the centriole, and the [[cell (biology)|cell]] itself (defined by the [[plasma membrane]]) may also be an example of structural inheritance.
Various additional examples of structural inheritance are presented in the recent book [[Origination of Organismal Form]].
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