FlyBase curator comment: this entry is used to capture phenotypic information when the particular allele (or allele combination) used by the author could not be determined but the context of the experiment suggests that the phenotype being described is some kind of loss of function.
Clones in the central brain derived from single cell mutant neuroblasts show an ectopic self-renewal phenotype, containing multiple neuroblast cells (wild-type single cell clones only contain one neuroblast).