title: Prenatal identification of a marker chromosome 16 by chromosome microdissection and reverse FISH.
abstract: Prenatal cytogenetic analysis of cultured amniocytes was performed after an increased foetal nuchal translucency thickness was detected by ultrasound in week 17 of a pregnancy. Analysis of GTG-banded chromosomes showed a small marker chromosome in six of the 12 colonies analysed. The supernumerary abnormal chromosome appeared to be positive with DA/DAPI staining and C-banding. The parents' karyotypes were normal. Using microFISH and FISH with band-specific probes, we found the marker appeared to be derived from chromosome region (16)(p13.1-->q12.2). Accurate identification of the marker chromosome was important for prenatal counselling: the marker chromosome contained euchromatic sequences, the foetus was carrying mosaic trisomy 16, and based on the literature the prognosis for the foetus was unfavourable and the pregnancy was terminated.
authors.affiliation: Department of Biomedical Genetics, University Medical Centre, Utrecht, The Netherlands.
authors.forename: Joke
authors.initials: J
authors.lastname: de Pater
authors.forename: Carla
authors.initials: C
authors.lastname: Van der Sijs-Bos
authors.forename: Mieke
authors.initials: M
authors.lastname: Prins
authors.forename: Jan
authors.initials: J
authors.lastname: Derks
authors.forename: Jozefa
authors.initials: J
authors.lastname: Albrechts
authors.forename: John
authors.initials: J
authors.lastname: Engelen
mesh_terms: D000328:Adult; D000649:Amniocentesis; D002871:Chromosome Banding; D002885:Chromosomes, Human, Pair 16; D020732:Cytogenetic Analysis / Q000379:methods*; D005260:Female; D005817:Genetic Counseling; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D042282:Microdissection; D009030:Mosaicism; D048208:Nuchal Translucency Measurement; D011247:Pregnancy; D014314:Trisomy / Q000175:diagnosis*