gnu³⁰⁵ mutant females lay embryos that have few giant nuclei (due to inability to undergo mitosis); females carrying the gnu^T:Avic\GFP rescue construct lay embryos that do not display any defects in embryonic mitoses, embryos from gnu³⁰⁵ mothers carrying the gnu^{9A.T:Avic\GFP} construct show only partial rescue - the embryos undergo mitosis but most show defects in early cycles or in blastoderm stage.

The progression through meiosis upon egg activation is delayed (condensed phase of metaphase I persists longer than in wild-type and the metaphase I/anaphase I transition is delayed) in gnu³⁰⁵;gnu^{9A.T:Avic\GFP} oocytes, the morphology of chromosomes at metaphase I is frequently aberrant and defects in meiotic chromosome segregation are also observed.

Nuclear division fails in the earliest stages of development of gnu³⁰⁵ mutant embryos, producing embryos with a few giant nuclei.

Cleavage stage embryos from gnu^Z3-3770A/gnu³⁰⁵ or gnu^Z3-0591/gnu³⁰⁵ mothers, have giant polyploid nuclei.

Mutant eggs and embryos contain a small number of giant nuclei. Females doubly mutant for gnu³⁰⁵ and fs(1)Ya⁶ or fs(1)Ya² are indistinguishable from the fs(1)Ya embryos in terms of nuclear morphology. Females doubly mutant for gnu³⁰⁵ and fs(1)Ya⁵ or fs(1)Ya^14-77 (leaky fs(1)Ya mutations) exhibit gnu-like or fs(1)Ya-like nuclear morphology.

Homozygous females lay eggs in which the meiotic products and the pronucleus undergo extensive DNA replication resulting in a 'giant nuclei' phenotype. dhd^J5 does not suppress the premature initiation of DNA synthesis in double mutants.

Eggs derived from homozygous mothers have giant nuclei, which have partial conjugation of the chromatids in the majority of cases, and arrangement of chromatin in a longitudinal order.

Mothers homozygous for png² and heterozygous for gnu³⁰⁵ produce embryos with less than 6 giant polyploid nuclei.

The meiotic products in unfertilised eggs laid by homozygous females undergo DNA synthesis and the eggs develop giant nuclei. These eggs are cytologically indistinguishable from eggs laid by homozygous females allowed to mate with males. Centrosomes that can nucleate microtubules into asters are seen in unfertilised eggs laid by homozygous females. Eggs from homozygous females can be inseminated, and when they are the sperm nucleus undergoes DNA synthesis, participating in the formation of giant nuclei.

Embryos derived from gnu³⁰⁵ mutant females show uncoupling of nuclear division from other cytoplasmic events of mitosis during early cleavage; DNA replicates, centrosomes divide and migrate to the cortex but no nuclear division occurs, and 2-4 giant nuclei are formed. Larval mitoses appear normal.

maternal-effect lethal. Embryos produced by homozygous or hemizygous females exhibit normal levels of DNA synthesis, but do not display normal nuclear division; a small number of giant nuclei formed. Cytoplasmic elements such as centrosomes, microtubules and actin appear to attempt to follow the normal developmental program, demonstrating that control of nuclear and cytoplasmic components of syncytial nuclear divisions can be uncoupled.