Imprecise excision of the progenitor insertion has resulted in a deletion which affects both Gyc76C and HLH106 (neighbouring genes). The deletion extends 697bp into the HLH106 open reading frame, up to amino acid residue 233 in exon 3 (the next in-frame start codon is at amino acid residue 265). The deletion also removes the predicted first exon of Gyc76C.