Embryos produced by "ring-sensitive" (RS) females carrying R(Y)F from either parent die during embryogenesis, probably by the pre-blastoderm stage. The embryos appear abnormal; the nuclei migrate to the peripheral cytoplasm, but are not as numerous or regularly spaced as in wild-type embryos, and many are pycnotic or have irregularly tattered chromatin.

Pre-blastoderm embryos produced by so-called ring-sensitive females and carrying R(Y)F, either paternal or maternal in origin, are disorganized and fail to develop; the genetic basis of maternal ring sensitivity is complex (Stone).