Open AccessCytology of aberrations induced by X‐rays in oocytes of Drosophila melanogaster.
Author(s) -
SAVONTAUS MARJALIISA
Publication year - 1981
Publication title -
hereditas
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.819
H-Index - 50
eISSN - 1601-5223
pISSN - 0018-0661
DOI - 10.1111/j.1601-5223.1981.tb01747.x
Subject(s) - biology , nondisjunction , chiasma , meiosis , chromatid , autosome , drosophila melanogaster , genetics , chromosome , centromere , metaphase , x chromosome , aneuploidy , gene
After X‐ray treatment (3000r) of early meiotic stages of oocytes of Drosophila melanogaster , the metaphase‐I configurations were analyzed cytologically. The frequency of oocytes with achiasmatic X chromosomes or major autosomes with a chromosome arm lacking a chiasma was increased by irradiation compared to the control oocytes. Aberrant meiotic configurations were observed in 15% of the oocytes. They included chromosome and chromatid fragments, heterologous exchanges, and misorien‐tation of the chromosomes. Oocytes with simultaneous nondisjunction of two chromosome pairs were observed. In other types of displacements, the misorientating chromosomes were passively following their homologues, suggesting malfunction of the centromeres.