Published online by Cambridge University Press: 14 April 2009
A genetic fine-structure experiment on Drosophila melanogaster is described, which makes use of a lethal selective system which permits survival only of recombinants in the ma-l region, including exchanges between site mutants of ma-l. On the basis of prior mapping information, the experiment was designed to select for ma-l double mutant recombinants. Utilizing a pair of complementing ma-l mutants, double mutant meiotic products were recovered whose complementation properties provide independent support for the single-cistron, allele complementation model of organization of the maroon-like region inferred from other experiments described earlier.