Definition of polytene in US English:



  • Relating to or denoting a giant chromosome which is composed of many parallel copies of the genetic material, as found in Drosophila fruit flies where they are much used in genetic research.

    • ‘Two of those contained repetitive sequence and hybridized to the centromeres of the polytene chromosomes.’
    • ‘Anopheline mosquitoes, like Drosophila, are renowned for the presence of polytene chromosomes and chromosomal inversions.’
    • ‘Cytogenetic studies of mitotic and polytene chromosomes, allozyme data, and crossing studies indicate that An. dirus A and C are very closely related.’
    • ‘This was first recognized more than a half century ago in cytological studies of lampbrush chromosomes in amphibian oocytes and polytene chromosomes in insects.’
    • ‘The structures of rearrangements were defined by mitotic chromosome staining as well as by genetic and polytene chromosome analysis.’
    • ‘It was mapped in Drosophila by polytene chromosome in situ to 3L heterochromatin.’


1930s: from poly- ‘many’ + -tene (from Greek tainia ‘band, ribbon’) denoting stages of the first meiotic division.