In Cdc27L7123 mutants, there is a high proportion of cells in a metaphase-like state (a ratio of 8.7 metaphase:anaphase compared to 2.8 in wild-type). Along with the low proportion of cells in anaphase, this suggests that Cdc27L7123 cells arrest or delay in metaphase. The extent of chromosome condensation observed indicates that cells have been delayed in metaphase for a period of time. Cdc27L7123 anaphase cells are frequently disorganised, with chromosomes lagging along the spindle. A low frequency (~3% of mitoses) of polyploid cells are also found in Cdc27L7123 cells. In Cdc27L7123 larval stage brains the sister chromosomes of at least one chromosome are found to be separated in 20% of all mitotic figures. 19% of Cdc27L7123 mitotic cells are found to contain a 4N complement of chromosomes in which there are four sites of hybridization indicating that the sister chromosomes are separated. This is compared to a frequency of 0.4% in wild-type metaphase cells. In mitotic Cdc27L7123 cells, the centromeric regions of the two pairs of major autosomes are present as a series of four separate pairs of dots, indicative of chromosome separation. Approximately 3.9% of Cdc27L7123 cells contain a replicated tetraploid set of chromosomes. Chromatin in Cdc27L7123 mitotic cells is distributed in a broad band. Cdc27L7123 cells exhibit overcondensed chromosomes. Up to 16 separated kinetochores of sister chromosomes are observed in Cdc27L7123 cells, similar to the phenotype observed in polo hypomorphs.
Homozygous flies occasionally survive to adulthood. These escapers have many eye and bristle defects, are invariably sterile and only live for a few days.