When homozygous, wild type at 14oC, 18oC, and 25oC. ci+C/Df(4)M wild type at 26oC; very few flies show thinning or interruption of L4 at 14oC. ci+C/ci1 wild type at 26oC; some flies show thinning or interruption at 14oC. ci+C/ciW causes significant thinning or interruption of L4 at 26oC. RK3.
Relative strengths of wild-type isoalleles are ci+C > ci+5 > ci+3 > ci+2.