It is shown that the frequency of spontaneous male recombination in two different lines of Drosophila melanogaster (OKI and T-007) are not subject to an interchromosomal effect. Second-chromosome male recombination in these lines was not affected by heterozygosity for the multiple third-chromosome inversions In(3LR)TM3 or In(3LR)Ubx, which do affect recombination in females. It seems, therefore...

NTEREST in interchromosomal effects on crossing over in Drosophila melanoIgaster has been renewed recently (COOPER, ZIMMERING and KRIVSHENKO 1955; OKSALA 1958; HART and SANDLER 1961; RAMEL 1962; SUZUKI 1962a; ROBERTS 1962). As a result of the new approaches taken in these studies, two general types of mechanisms, one physiological in nature ( STEINBERG and FRASER 1944; RAMEL 1962; ROBERTS 1962)...

Structural chromosome aberrations or chromosome mutations represent apart from aneuploidies the most frequent pathologic findings in applied chromosome diagnostics. But they also occur as combinations of both types as in unstable rearrangements or in chaotic karyotypes of early stages of embryonic development. Depending on the indication for chromosome analysis—child with developmental retardat...

Structural chromosome aberrations or chromosome mutations represent apart from aneuploidies the most frequent pathologic findings in applied chromosome diagnostics. But they also occur as combinations of both types as in unstable rearrangements or in chaotic karyotypes of early stages of embryonic development. Depending on the indication for chromosome analysis—child with developmental retardat...

Structural chromosome aberrations or chromosome mutations represent apart from aneuploidies the most frequent pathologic findings in applied chromosome diagnostics. But they also occur as combinations of both types as in unstable rearrangements or in chaotic karyotypes of early stages of embryonic development. Depending on the indication for chromosome analysis—child with developmental retardat...