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Chromosomal fragments transmitted through three generations in Oncopeltus (Hemiptera)

L E LaChance, M Degrugillier

    Science (New York, N.Y.)
    |October 10, 1969
    PubMed

    Insights

    X-rays induced chromosomal damage in milkweed bug sperm, causing sterility in offspring. This damage persisted across generations, confirming the unique holokinetic nature of their chromosomes.

    Area of Science:

    • Genetics
    • Radiation Biology
    • Entomology

    Background:

    • X-rays are known mutagens that can induce chromosomal aberrations.
    • Understanding chromosome behavior is crucial for genetic studies and evolutionary biology.
    • The milkweed bug (Oncopeltus fasciatus) is a model organism for genetic research.

    Purpose of the Study:

    • To investigate the effects of X-ray induced chromosomal fragments and translocations in Oncopeltus fasciatus.
    • To determine the heritability and persistence of these chromosomal aberrations through subsequent generations.
    • To confirm the holokinetic nature of milkweed bug chromosomes based on aberration persistence.

    Main Methods:

    • Adult milkweed bugs were exposed to X-rays to induce sperm mutations.
    • Meiotic cells of F(1), F(2), and F(3) generation males were analyzed.
    • Chromosomal fragments and translocations were identified and quantified.
    • Sterility levels in treated progeny were assessed.

    Main Results:

    • X-ray exposure resulted in detectable chromosomal fragments and translocations in the sperm of adult milkweed bugs.
    • These induced aberrations were observed in the meiotic cells of multiple subsequent generations (F(1), F(2), F(3)).
    • A high incidence of sterility was noted in the progeny of treated bugs.

    Conclusions:

    • Chromosomal fragments and translocations induced by X-rays in milkweed bugs are heritable.
    • The persistence of these aberrations across generations provides strong evidence for the holokinetic nature of Oncopeltus fasciatus chromosomes.
    • Radiation-induced chromosomal damage can lead to significant reproductive issues in insect populations.

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