Identification of satellited markers by microdissection and fluorescence in situ hybridization: a clinical case of isodicentric chromosome 22

Abstract Background The presence of small supernumerary marker chromosomes (sSMCs) in a karyotype leads to diagnostic questions because the resulting extra material may cause abnormal development depending on origin duplication/triplication. Because SMCs are so small, their cannot be determined by conventional cytogenetic techniques, and new molecular methods necessary. Here, we applied target approach chromosome rearrangement analysis isolating interest via microdissection using it fluorescence situ hybridization (FISH) as probe combination with whole-chromosome painting probes. This allows identify origins both euchromatin repeat-rich regions marker. Case presentation We report case an adult male congenital atresia rectum anus, anotia, external auditory canal along hearing loss. Karyotyping FISH probes acrocentric constructed library reliably identified additional some metaphases: mos 47,XY,+idic(22)(q11.2)[14]/46,XY [23]. Conclusion propose use libraries microdissected enriched repeated sequences. show that methodology is successful identifying composition satellited chromosome.