Increases penetrance by 8% and expressivity by 91% for the tumorous-head trait.
E(tuh-1)1 is an enhancer of phenotype of tuh1unspecified
Acts in trans to Abd-Biab9-tuh-3 to increase maternal effect of tuh1 on transformation of head to abdominal structures.
Dramatically increases the frequency of head defects in animals derived from tuh1h females, and shifts the distribution of thoracic defects in the tumorous-head (CT) strain (whose phenotype may depend on tuh1 and Abd-Biab9-tuh-3) anteriorly.