The - Strain Contains a Fixed Translocation Involving the and Chromosomes.

We discovered that a commonly used balancer chromosome - - exists as an uncharacterized translocation between the progenitor chromosome and a normal chromosome . Genetic and cytological data evidence show that ( ; ) translocates about 5% of chromosome material to an entire chromosome , thus the large "chromosome " segregant is lethal without the small "chromosome " segregant, though the latter is viable and fertile without the former. We characterize this balancer chromosome to inform molecular-geneticists of the structure as it may affect their use of this balancer chromosome and the interpretations of their results.