P-element insertion in the hop locus.
lethal (with hop25)
lethal | recessive
5% viable in transheterozygous combination with hop25.
Melanotic tumour formation.
hopM637/hop25 has lethal phenotype, enhanceable by upd1YM55
Viability of hop25/hopM637 flies is reduced to 0% if the flies also carry osupd-4.
K. Watson and R. Denell.