[Drosophila] Genetic marker

[Gustavo Betini]

Dear all,

I want to use a genetic marker in /Drosophila melanogaster/ to follow 
individuals through several generations that will be breeding with wild 
types. I thought about a phenotypically co-dominant marker with minimal 
effects on fitness, or something like spa or sv whose heterozygous seems 
to be easily recognizable. Any idea?

Any help would be much appreciated,

Gustavo S. Betini
Dept of Integrative Biology
University of Guelph, Canada