A stable acentric marker chromosome: possible existence of an intercalary ancient centromere at distal 8p

Am J Hum Genet. 1994 Dec;55(6):1202-8.


A centromere is considered to be an essential chromosomal component where microtubule-kinetochore interaction occurs to segregate sister chromatids faithfully and acentric chromosomes are unstable and lost through cell divisions. We report a novel marker chromosome that was acentric but stable through cell divisions. The patient was a 2-year-old girl with mental retardation, patent ductus arteriosus, and mild dysmorphic features. G-banded chromosome analysis revealed that an additional small marker chromosome was observed in all 100 cells examined. By the reverse-chromosome-painting method, the marker was found to originate from the distal region of 8p, and a subsequent two-color FISH analysis with cosmid probes around the region revealed that the marker was an inverted duplication interpreted as 8pter-->p23.1::p23.1-->8pter. No centromeric region was involved in the marker. By FISH, no alpha-satellite sequence was detected on the marker, while a telomere sequence was detected at each end. Anti-kinetochore immunostaining, using a serum from a patient with CREST (calcinosis, Raynaud syndrome, esophageal dismotility, sclerodactyly, and telangiectasia) syndrome, showed a pair of signals on the marker, which indicated that a functional kinetochore was present on the marker. The analysis of this patient might suggest the possibility that an ancient centromere sequence exists at distal 8p (8p23.1-pter) and was activated through the chromosome rearrangement in the patient.

Publication types

  • Case Reports

MeSH terms

  • Abnormalities, Multiple / genetics
  • CREST Syndrome / immunology
  • Centromere / chemistry
  • Centromere / genetics*
  • Child, Preschool
  • Chromosome Aberrations / genetics*
  • Chromosome Banding
  • Chromosomes, Human, Pair 8 / genetics*
  • Chromosomes, Human, Pair 8 / ultrastructure
  • Ductus Arteriosus, Patent / genetics
  • Female
  • Genetic Markers
  • Humans
  • In Situ Hybridization, Fluorescence
  • Kinetochores / chemistry
  • Kinetochores / immunology
  • Nuclear Proteins / chemistry
  • Nuclear Proteins / immunology
  • Polymerase Chain Reaction


  • Genetic Markers
  • Nuclear Proteins