Gen

Gen adalah jujukan linear genom DNA yang merupakan unit berfungsi pada kromosom atau plasmid. Keseluruhan maklumat dan sifat bagi struktur dan fungsi sesuatu organisma yang boleh diwarisi secara keturunan dikodkan dalam gennya.^[1]^[2] Bagi sesetengah maklumat yang dikodkan oleh gen menentukan hanya satu ciri, tetapi sesetengah lokus (lokasi) bagi gen yang sama boleh membawa maklumat yang berlainan. Gen yang mempunyai maklumat yang berlainan pada lokus yang sama dinamakan alel.^[3]

Hal ini mula diungkapkan dalam makalah berbahasa Jerman (Gen) ditulis ahli botani Denmak Wilhelm Johannsen tahun 1909 menerbitkan dari kata Pangene diakar Bahasa Yunani Kuno γόνος gonos "menjadikan" berkaitan dengan teori pangenesis diusulkan Charles Darwin.^[4]^[5]

^ Pearson H (2006). "Genetics: what is a gene?". Nature. 441 (7092): 398–401. doi:10.1038/441398a. PMID 16724031.
^ Elizabeth Pennisi (2007). "DNA Study Forces Rethink of What It Means to Be a Gene". Science. 316 (5831): 1556–1557. doi:10.1126/science.316.5831.1556. PMID 17569836.
^ Black, Jacquelyn G. (2002). Microbiology: principles and explorations. Edisi kelima. ISBN 0-471-38729
^ Magner, Lois N. (2002). A History of the Life Sciences (ed. Third). Marcel Dekker, CRC Press. m/s. 371. ISBN 978-0-203-91100-6.
^ Johannsen W (1909). Elemente der exakten Erblichkeitslehre [Elements of the exact theory of heredity] (dalam bahasa German). Jena, Germany: Gustav Fischer. m/s. 124.CS1 maint: unrecognized language (link) From p. 124: "Dieses "etwas" in den Gameten bezw. in der Zygote, … – kurz, was wir eben Gene nennen wollen – bedingt sind." (This "something" in the gametes or in the zygote, which has crucial importance for the character of the organism, is usually called by the quite ambiguous term Anlagen [primordium, from the German word Anlage for "plan, arrangement ; rough sketch"]. Many other terms have been suggested, mostly unfortunately in closer connection with certain hypothetical opinions. The word "pangene", which was introduced by Darwin, is perhaps used most frequently in place of Anlagen. However, the word "pangene" was not well chosen, as it is a compound word containing the roots pan (the neuter form of Πας all, every) and gen (from γί-γ(ε)ν-ομαι, to become). Only the meaning of this latter [i.e., gen] comes into consideration here ; just the basic idea – [namely,] that a trait in the developing organism can be determined or is influenced by "something" in the gametes – should find expression. No hypothesis about the nature of this "something" should be postulated or supported by it. For that reason it seems simplest to use in isolation the last syllable gen from Darwin's well-known word, which alone is of interest to us, in order to replace, with it, the poor, ambiguous word Anlage. Thus we will say simply "gene" and "genes" for "pangene" and "pangenes". The word gene is completely free of any hypothesis ; it expresses only the established fact that in any case many traits of the organism are determined by specific, separable, and thus independent "conditions", "foundations", "plans" – in short, precisely what we want to call genes.)

[Pearson_2006-1] Pearson H (2006). "Genetics: what is a gene?". Nature. 441 (7092): 398–401. doi:10.1038/441398a. PMID 16724031.

[Rethink-2] Elizabeth Pennisi (2007). "DNA Study Forces Rethink of What It Means to Be a Gene". Science. 316 (5831): 1556–1557. doi:10.1126/science.316.5831.1556. PMID 17569836.

[3] Black, Jacquelyn G. (2002). Microbiology: principles and explorations. Edisi kelima. ISBN 0-471-38729

[4] Magner, Lois N. (2002). A History of the Life Sciences (ed. Third). Marcel Dekker, CRC Press. m/s. 371. ISBN 978-0-203-91100-6.

[Johannsen-5] Johannsen W (1909). Elemente der exakten Erblichkeitslehre [Elements of the exact theory of heredity] (dalam bahasa German). Jena, Germany: Gustav Fischer. m/s. 124.CS1 maint: unrecognized language (link) From p. 124: "Dieses "etwas" in den Gameten bezw. in der Zygote, … – kurz, was wir eben Gene nennen wollen – bedingt sind." (This "something" in the gametes or in the zygote, which has crucial importance for the character of the organism, is usually called by the quite ambiguous term Anlagen [primordium, from the German word Anlage for "plan, arrangement ; rough sketch"]. Many other terms have been suggested, mostly unfortunately in closer connection with certain hypothetical opinions. The word "pangene", which was introduced by Darwin, is perhaps used most frequently in place of Anlagen. However, the word "pangene" was not well chosen, as it is a compound word containing the roots pan (the neuter form of Πας all, every) and gen (from γί-γ(ε)ν-ομαι, to become). Only the meaning of this latter [i.e., gen] comes into consideration here ; just the basic idea – [namely,] that a trait in the developing organism can be determined or is influenced by "something" in the gametes – should find expression. No hypothesis about the nature of this "something" should be postulated or supported by it. For that reason it seems simplest to use in isolation the last syllable gen from Darwin's well-known word, which alone is of interest to us, in order to replace, with it, the poor, ambiguous word Anlage. Thus we will say simply "gene" and "genes" for "pangene" and "pangenes". The word gene is completely free of any hypothesis ; it expresses only the established fact that in any case many traits of the organism are determined by specific, separable, and thus independent "conditions", "foundations", "plans" – in short, precisely what we want to call genes.)

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