A C to A alteration at position 3R:15 ,241,548 (BDGP Release 6) generating a premature stop codon predicted to truncate the 2767 amino acid tefu polypeptide after residue 162.
Nucleotide substitution: C15241548A.
A spontaneous mutant allele that was segregating in the isogenized FRT82B progenitor strain used in a cell competition genetic screen.