bk1 << dpld << sax << bk2

Df(2R)cn83c/Df(2R)CA53 embryos are usually wild-type, but sometimes have segmentation defects and denticles in the third thoracic segment that resemble abdominal denticles. Df(2R)CA53/Df(2R)cn83c ; Scm¹/+ embryos lack terminal structures and are U-shaped. Denticle belts of the 3rd to 7th abdominal segments are transformed posteriorly.

Recovered as apparent cn double recombinants from test crosses of dysgenic-type males that were heterozygous for a maternally derived dp b cn bw second chromosome and paternally derived autosomes extracted from natural populations and capable of promoting male recombination.

The Df(2R)cn83c chromosome may act as a dominant suppressor of telomeric silencing (assayed using the effect of the chromosome on the eye colour phenotype of flies carrying "P{w^var}KR3-2", a stable "brown-red" variant of the P{3'WP-2,w^var}2Lt insertion), but the eye colour phenotype in the presence of Df(2R)cn83c overlaps the eye colour phenotype in a wild-type background so it cannot be unequivocally demonstrated that the deficiency chromosome uncovers a suppressor of telomeric silencing. In addition, any suppression is a false positive result (the suppressor is not within the bounds of the deficient region) because the region of the deficiency is covered by one or more nonsuppressing deficiencies.