Further Studies on the unextended (uex) Mutation of Drosophila melanogaster

A spontaneous mutation, unextended (uex), of Drosophila melanogaster produced a phenotype with unextended wings, but the wings were extended and expanded when mutant pharate adults were placed in water and removed from the pupal cases. In the present study, three mutations (m, ct and vg) all with abnormal wing phenotypes were each combined with uex, and the wing phenotypes in the doubly homozygous flies were examined in adults and pharate adults placed in water. Basically no interactions between the mutations examined were observed : simply combined phenotypic abnormalities were observed in all the cases. The uex vg adult wings showed the characteristics of the two mutations combined but the pharate adult wings when artificially expanded in water showed the characteristics of only the vg mutation. Possible causes are discussed.