A functional marker centromere with no detectable alpha-satellite, satellite III, or CENP-B protein: activation of a latent centromere?
We report the investigation of an unusual human supernumerary marker chromosome 10 designated "mar del(10)." This marker is present together with two other marker chromosomes in the karyotype of a boy with mild developmental delay. It has a functional centromere at a primary constriction and is mitotically stable. Fluorescence in situ hybridization (FISH) using alpha-satellite and satellite III DNA as probes failed to detect any signal at the primary constriction site. CENP-B protein could not be demonstrated, although the presence of at least some centromeric proteins was confirmed using a CREST antiserum. Consideration of these and other cytogenetic and FISH results supports a mechanism of formation of the mar del(10) chromosome involving the activation of a latent intercalary centromere at 10q25.
Voullaire
L E
LE
Murdoch Institute for Research into Birth Defects, Royal Children's Hospital, Parkville, Victoria, Australia.
Slater
H R
HR
Petrovic
V
V
Choo
K H
KH
D000906:Antibodies / Q000276:immunology; D001324:Autoantigens; D002478:Cells, Cultured; D002503:Centromere / Q000276:immunology; D051936:Centromere Protein B; D002675:Child, Preschool; D002868:Chromosomal Proteins, Non-Histone / Q000032:analysis*; D002879:Chromosomes, Human, Pair 10; D015342:DNA Probes; D004276:DNA, Satellite / Q000032:analysis*; D004268:DNA-Binding Proteins; D002658:Developmental Disabilities / Q000235:genetics*; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D007621:Karyotyping; D008297:Male; D009006:Monosomy
D000906:Antibodies; D001324:Autoantigens; C497926:CENPB protein, human; D051936:Centromere Protein B; D002868:Chromosomal Proteins, Non-Histone; D015342:DNA Probes; D004276:DNA, Satellite; D004268:DNA-Binding Proteins