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Testing for nondisjunction in the mouse.

A C Chandley·R M Speed
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Abstract

Tests for nondisjunction have been carried out in male and female mice. Ten-day fetal progeny of control and treated adults have been karyotyped to establish spontaneous and induced levels of aneuploidy. In males, the effects of 100 rad x-rays on type A spermatogonia and early primary spermatocytes, and the effects of Mitomycin C (2 mg/kg) on early primary spermatocytes, have been tested. The results show insensitivity of primary spermatocytes to both agents, but a 3.5-fold increase in nondisjunction following spermatogonial irradiation. In females, comparisons have been made between young controls, young x-rayed (5 rad), aged controls and aged x-rayed (5 rad) animals. The "ageing effect" on nondisjunction is observed, but too few fetuses have been analyzed to reach conclusions regarding enhancement of nondisjunction levels by low doses of x-rays.

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Abnormalities, Radiation-InducedAneuploidyAnimalsChromosome AberrationsChromosome DisordersFemaleGenetic TechniquesGestational AgeMaleMiceMitomycinsMosaicismSpermatozoaTrisomyX-RaysJournal Article

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A C Chandley, R M Speed. 1979. Testing for nondisjunction in the mouse.. https://doi.org/10.1289/ehp.7931123

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