A stable acentric marker chromosome: Possible existence of an intercalary ancient centromere at distal 8p
- Saitama Children`s Medical Center, Iwatsuki (Japan)
- Kitazato Univ., Tokyo (Japan)
- Nagasaki Univ. School of Medicine (Japan)
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 {yields} p23.1::p23.1 {yields} 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.
- OSTI ID:
- 56732
- Journal Information:
- American Journal of Human Genetics, Journal Name: American Journal of Human Genetics Journal Issue: 6 Vol. 55; ISSN AJHGAG; ISSN 0002-9297
- Country of Publication:
- United States
- Language:
- English
Similar Records
The distal 8p deletion (8)(p23.1): A common syndrome associated with cogenital heart defect and mental retardation?
The same molecular mechanism at the maternal meiosis I produces mono- and dicentric 8p duplications