Embryos derived from BicD1/BicD2 mothers show a duplication of posterior structures and a lack of anterior structures. These embryos lack macrophages. Apoptotic cells accumulate at the ventral surface of the central nervous system (CNS), and subperineural glia contain an abundance of apoptotic cells. Single unengulfed apoptotic cells are also seen inside the CNS. The number of subperineural glia per abdominal segment is not significantly different from wild-type in stage 16 embryos.
Ectopic nos activity at the anterior pole of embryos derived from BicD1 mutant females blocks bcd protein expression from bcdΔ transcripts but not from bcd+ transcripts. None of the embryos bearing the bcdΔ mRNA display the bcd phenotype.