polyteneadj.
/ˈpɒlᵻtiːn/, U.S. /ˈpɑləˌtin/ Cell Biology.
Designating or relating to giant chromosomes found in certain meiotic interphase nuclei (esp. in dipterous insects) and composed of many chromatids side by side.The large number of chromatids in such a chromosome makes evident banding patterns that can be used for the identification and mapping of chromosomes.
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the world > life > biology > biological processes > genetic activity > genetic components > [adjective] > chromosome > types of chromosome
supernumerary1907
autosomal1911
lampbrush1911
trisomic1921
hexasomic1922
tetrasomic1922
monosomic1926
polytene1935
polytenic1952
polysomal1962
polytenized1974
1935 P. C. Koller in Proc. Royal Soc. B. 118 372 We can regard these chromosomes as corresponding with paired pachytene chromosomes at meiosis in which the intercalary parts between chromosomes have been stretched and separated into smaller units, and in which, instead of two threads lying side by side, we have 16 or even more. Hence they are ‘polytene’ rather than pachytene; I do not, however, propose to use this term; I shall refer to them as ‘multiple threads’.
1959 C. M. M. Begg Introd. Genetics iii. 27 The specificity of this pairing is shown very strikingly in the case of the exceptional polytene threads of the much enlarged salivary gland nuclei of Diptera.
1971 Nature 21 May 184/2 Individuals of the species which breeds in freshwater can only be identified with certainty by the banding patterns of their polytene chromosomes.
1976 P. Bell & D. Coombe tr. Strasburger's Textbk. Bot. (new ed.) 31 (caption) Giant chromosome, polytene and consisting of about 2048 strands, from the suspensor of the embryo of Phaseolus vulgaris.
1995 D. Kipling Telomere vi. 120 The ciliate life cycle... Development begins with multiple rounds of replication to form polytene chromosomes. Following this much of the genome is eliminated.
This entry has been updated (OED Third Edition, September 2006; most recently modified version published online March 2022).
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adj.1935