[The comparative analysis of the mutational variability and instability of the thi, Bd strains induced by exogenous viral DNA in Drosophila melanogaster]. / Sravnitel'nyi analiz mutatsionnoi izmenchivosti i nestabil'nosti linii thi, Bd, indutsirovannykh ékzogennoi virusnoi DNK, u Drosophila melanogastrer.

ABSTRACT

Frequency of reversions to wild type varies for thi and its derivatives from 10(-2) to 10(-5). A broad spectrum of mutations arises in thi alleles and thi+ revertants. Among them there are r, w, Bd and new mutations causing scalloped wings with thickened veins in all the autosomes. In the offspring of a Cy/thi 1 male a fly is found carrying a thi 1 allele in the Cy chromosome; this is not caused by crossing-over, but probably by a transposition. Mutations in the thi, Bd strains and their derivatives are supposed to be caused by small insertion. The nature of these insertions are under discussion.