At 25oC, the survival rates of homozygotes are: adult survival - 1%, eclosion - 8%, pupation 19%. At 18oC, the survival rates of homozygotes are: adult survival - 1%, eclosion - 53%, pupation 80%. Ptp69D13 embryos show motor axon defects; 10% of ISNb axons, 3% of ISN axons, 5% of SNa axons and 1% of SNc axons show defects.