Meiotic aneuploidy: its origins and induction following chemical treatment in Sordaria brevicollis.
نویسندگان
چکیده
A system suitable for the detection of meiotic aneuploidy is described in which various different origins of the aneuploidy can be distinguished. Aneuploid meiotic products are detected as black disomic spores held in asci containing all the products of a single meiosis. Aneuploidy may result from nondisjunction or from a meiosis in which an extra replica of one of the chromosomes has been generated in some other way, e.g., extra replication. By using this system it has been shown that pFPA treatment increase aneuploidy, primarily through an effect on nondisjunction. Preliminary results with trifluralin have indicated that this compound, too, may increase aneuploidy. There is a good possibility that the system can be further developed to permit a more rapid screening using a random plating method; this will allow a more efficient two-part analysis of the effects of compounds under test.
منابع مشابه
The Genetics of a Probable Insertional Translocation in SORDARIA BREVICOLLIS.
A chromosome rearrangement has been isolated and characterized in Sordaria brevicollis. Crosses to spore color mutants on each of the seven linkage groups have enabled the breakpoints to be mapped. The simplest hypothesis to account for the results is that a piece of linkage group VI has been translocated to linkage group V and inserted 2.7 map units from its centromere. Previous reports of mar...
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ورودعنوان ژورنال:
- Environmental Health Perspectives
دوره 31 شماره
صفحات -
تاریخ انتشار 1979