Popis: |
In an inbred line of Drosophila melanogaster (Oregon, our code “2”) a second inversion has been induced by X-rays (symbol In(1) Lu- y wa ex vf-2). The inversion is small (about 40 bands) and is located between w and ex (bands 3E to 4C). Inversion heterozygous females have been scored for recombination frequency, primary and secondary non-disjunction. The In (1) Lu-2 heterozygous females showed decreased recombination frequency as far as to v. The total recombination (y-f) was decreased to about half. The primary non-disjunction was not detectably altered compared to that characterizing regular gene order, but the secondary non-disjunction was slightly enhanced and a value of 7% with no excess of XY males was obtained. Thus, both similarities and dissimilarities, as compared to regular gene order and the large proximal inversion In (1) Lu-1 in the same genome, were obvious and are discussed. |