Does not cause a dominant negative effect in a wild-type background. However, 98% of embryos derived from Df(2L)TW119/+ females carrying dl222-342.Hsp83.T:Ecol\lacZ are dorsalised and do not hatch, and 89% of embryos derived from cact7/+ females carrying dl222-342.Hsp83.T:Ecol\lacZ are weakly ventralised and do not hatch.