The I.3.2 developmental mutant has a single nucleotide deletion in the gene centromere identifier.

The mutation I.3.2 was previously identified in a FLP/FRT screen of chromosome 2R for conditional growth regulators. Here we report the phenotypic characterization and genetic mapping of I.3.2 by undergraduate students participating in Fly-CURE, a pedagogical program that teaches the science of genetics through a classroom research experience. We find that creation of I.3.2 cell clones in the developing eye-antennal imaginal disc causes a headless adult phenotype, suggestive of both autonomous and non-autonomous effects on cell growth or viability. We also identify the I.3.2 mutation as a loss-of-function allele of the gene centromere identifier ( cid ), which encodes centromere-specific histone H3 variant critical for chromosomal segregation.