The C(1)DX-P{hs-hid}7 chromosome has no dominant lethal effect even at 29[o]C, but displays fully penetrant dominant lethality (due to expression of hid from P{hs-hid}7) when embryos older than 7 hours are subjected to a 1 hour heat shock via immersion of culture vials into a 37[o]C water bath.
