title: Origin of a prenatal mosaic supernumerary neocentromeric derivative chromosome 13 determined by QF-PCR.
abstract: Neocentromeres are mitotically stable human derivative centromeres without alpha-satellite DNA which are able to provide stability to rearranged chromosome fragments that would otherwise be acentric and rapidly lost. A female fetus was found to be mosaic for a supernumerary marker chromosome: 47,XX,+mar[3]/46,XX[36]. The marker was identified by fluorescence in situ hybridization and G-band as an inversion duplication of 13q21→13qter, with a neocentromere present at 13q21, in approximately 9% of colonies examined. Parental blood karyotypes were normal. QF-PCR performed on blood samples from both parents and the second amniotic fluid sample showed evidence of a second maternal allele at markers D13S258 (13q21) and D13S628 (13q31-q32), indicating formation at maternal meiosis I/II. This is the first reported case where the detection and origin of a low-level mosaic prenatal neo(13) were confirmed by QF-PCR.
authors.affiliation: Cytogenetics Laboratory, Diagnostic Services of Manitoba, Winnipeg, Manitoba, Canada. adawson@dsmanitoba.ca
authors.forename: A J
authors.initials: AJ
authors.lastname: Dawson
authors.forename: M
authors.initials: M
authors.lastname: Hryshko
authors.forename: D
authors.initials: D
authors.lastname: Konkin
authors.forename: S
authors.initials: S
authors.lastname: Bal
authors.forename: D
authors.initials: D
authors.lastname: Bernier
authors.forename: M
authors.initials: M
authors.lastname: Tomiuk
authors.forename: S
authors.initials: S
authors.lastname: Burnett
authors.forename: P
authors.initials: P
authors.lastname: Frosk
authors.forename: B N
authors.initials: BN
authors.lastname: Chodirker
authors.forename: K
authors.initials: K
authors.lastname: Chun
mesh_terms: D000328:Adult; D000649:Amniocentesis; D002503:Centromere; D058674:Chromosome Duplication; D007446:Chromosome Inversion; D002882:Chromosomes, Human, Pair 13; D005260:Female; D006801:Humans; D008297:Male; D009030:Mosaicism; D016133:Polymerase Chain Reaction; D011247:Pregnancy