TY - JOUR
T1 - Centromeric inactivation in a dicentric human Y;21 translocation chromosome
AU - Fisher, Andrew M.
AU - Al-Gazali, Lihadh
AU - Pramathan, T.
AU - Quaife, Roger
AU - Cockwell, Annette E.
AU - Barber, John C.K.
AU - Earnshaw, William C.
AU - Axelman, Joyce
AU - Migeon, Barbara R.
AU - Tyler-Smith, Chris
N1 - Funding Information:
Acknowledgements. We thank R. Renshaw, J.A. Crolla, C.M. Campbell, A.H. Herbert and P.A. Jacobs for help and useful discussions during the course of this work. W.C.F. was supported by The Wellcome Trust, B.R.M. was supported by NIH grant HD05465 and C.T.-S. was supported by the CRC.
PY - 1997
Y1 - 1997
N2 - A de novo dicentric Y;21 (q11.23;p11) translocation chromosome with one of its two centromeres inactive has provided the opportunity to study the relationship between centromeric inactivation, the organization of alphoid satellite DNA and the distribution of CENPC. The proband, a male with minor features of Down's syndrome, had a major cell line with 45 chromosomes including a single copy of the translocation chromosome, and a minor one with 46 chromosomes including two copies of the translocation chromosome and hence effectively trisomic for the long: arm of chromosome 21. Centromeric activity as defined by the primary constriction was variable: in most cells with a single copy of the Y;21 chromosome, the Y centromere was inactive. In the cells with two copies, one copy had an active Y centromere (chromosome 21 centromere inactive) and the other had an inactive Y centromere (chromosome 21 centromere active). Three different partial deletions of the Y alphoid array were found in skin fibroblasts and one of these was also present in blood. Clones of single cell origin from fibroblast cultures were analysed both for their primary constriction and to characterise their alphoid array. The results indicate that (1) each clone showed a fixed pattern of centromeric activity; (2) the alphoid array size was stable within a clone; and (3) inactivation of the Y centromere was associated with both full-sized and deleted alphoid arrays. Selected clones were analysed with antibodies to CENP-C, and staining was undetectable at both intact and deleted arrays of the inactive Y centromeres. Thus centromeric inactivation appears to be largely an epigenetic event.
AB - A de novo dicentric Y;21 (q11.23;p11) translocation chromosome with one of its two centromeres inactive has provided the opportunity to study the relationship between centromeric inactivation, the organization of alphoid satellite DNA and the distribution of CENPC. The proband, a male with minor features of Down's syndrome, had a major cell line with 45 chromosomes including a single copy of the translocation chromosome, and a minor one with 46 chromosomes including two copies of the translocation chromosome and hence effectively trisomic for the long: arm of chromosome 21. Centromeric activity as defined by the primary constriction was variable: in most cells with a single copy of the Y;21 chromosome, the Y centromere was inactive. In the cells with two copies, one copy had an active Y centromere (chromosome 21 centromere inactive) and the other had an inactive Y centromere (chromosome 21 centromere active). Three different partial deletions of the Y alphoid array were found in skin fibroblasts and one of these was also present in blood. Clones of single cell origin from fibroblast cultures were analysed both for their primary constriction and to characterise their alphoid array. The results indicate that (1) each clone showed a fixed pattern of centromeric activity; (2) the alphoid array size was stable within a clone; and (3) inactivation of the Y centromere was associated with both full-sized and deleted alphoid arrays. Selected clones were analysed with antibodies to CENP-C, and staining was undetectable at both intact and deleted arrays of the inactive Y centromeres. Thus centromeric inactivation appears to be largely an epigenetic event.
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U2 - 10.1007/s004120050240
DO - 10.1007/s004120050240
M3 - Article
C2 - 9254721
AN - SCOPUS:0030823567
SN - 0009-5915
VL - 106
SP - 199
EP - 206
JO - Chromosoma
JF - Chromosoma
IS - 4
ER -