Analysis of radiation-induced W chromosome aberrations in the codling moth, Cydia pomonella (L.), by fluorescence in situ hybridization techniques

The structure of the female sex-determining W chromosome was examined in wild-type females and in three mutant female lines of the codling moth, Cydia pomonella. The mutant lines were isolated from progeny of irradiated females using the abnormal appearance of sex chromatin body in female somatic polyploid nuclei as a cytogenetic marker. A detailed cytogenetic analysis was carried out using three different fluorescence in situ hybridization techniques: genomic in situ hybridization (GISH), comparative genomic hybridization (CGH), and fluorescence in situ hybridization (FISH) with the codling moth W-chromosome painting probe. The FISH techniques enabled us to identify the W chromosome and its fragments in mitotic and meiotic chromosome complements and thus helped us to resolve complicated W chromosome aberrations induced by irradiation.