EXTRACHROMOSOMAL ELEMENT DELTA IN DROSOPHILA MELANOGASTER . III: INDUCTION OF ONE-SIDED GAMETE RECOVERY FROM MALE AND FEMALE HETEROZYGOTES

Abstract

Males and females heterozygous for the Cy chromosome and certain other non-Cy second chromosomes produced only Cy-bearing progeny when the heterozygotes carried an appreciable amount of the extrachromosomal element delta.

EXTRACHROMOSOMAL ELEMENT DELTA IN DROSOPHILA MELANOGASTER. VII. RELATION TO FERTILITY IN A SECOND-CHROMOSOME LINE

“…The element denoted by delta in Drosophila melanogaster is no exception to the above. It was found because it kills flies carrying two sensitive second chromosomes (MINAMORI 1969a). Moreover, it does damage to the host chromosomes; it induces frequent lethal mutations (MINAMORI and ITO 1971 ) and dysfunctional gametes carrying counterpart chromosomes of the second chromosome in certain heterozygous males and females (MINAMORI 1970).…”

“…It was found because it kills flies carrying two sensitive second chromosomes (MINAMORI 1969a). Moreover, it does damage to the host chromosomes; it induces frequent lethal mutations (MINAMORI and ITO 1971 ) and dysfunctional gametes carrying counterpart chromosomes of the second chromosome in certain heterozygous males and females (MINAMORI 1970). Two variants of delta are known, delta b and delta r; each multiplies in the presence of a specific sensitive chromosome (MINAMORI 1971).…”

“…Moreover, it does damage to the host chromosomes; it induces frequent lethal mutations (MINAMORI and ITO 1971 ) and dysfunctional gametes carrying counterpart chromosomes of the second chromosome in certain heterozygous males and females (MINAMORI 1970). Two variants of delta are known, delta b and delta r; each multiplies in the presence of a specific sensitive chromosome (MINAMORI 1971). The multiplication is accelerated at higher temperatures and suppressed at lower temperatures.…”

“…An appreciable amount of delta b is transmitted through females and an undemonstrable amount through males of the sensitive lines. The association of delta with the sensitive lines is inseparable (MINAMORI 1969b(MINAMORI , 1972. Based on several lines of evidence, the senior author postulated that delta may be a copy of a chromosomal gene (s) or of a certain agent which is integrated inseparably into the chromosome; possibly a particulate DNA or RNA which multiplies autonomously and may be transmitted extrachromosomally (Zoc.…”