Stop codon have been introduced upstream of the GAGA repeats, with a frame shift in the pug coding region. The new open reading frame stops 16 codons downstream without reaching the GAGA repeats. The altered pugD coding region is predicted to encode a short peptide of 153 amino acids in which 137 are from the N terminus of pug and the extra 16 result from the frame shift.
Causes no pigment defects.
Position effect has been eliminated as a possible explanation for lack of phenotype by targeting the construct to different chromosomal locations at which the pugD phenotype has been reproduced using pugK-B.3.4.