Dicentric plasmids containing either two copies of centromere 4 or one copy of centromere 4 and one copy of centromere 3 in the yeast plasmid vector YRp17 were constructed in vitro and introduced into yeast cells by DNA transformation. The resulting colonies were heterogeneous for a mixed population of rearranged plasmids. The rearrangements always involved deletion of one or both centromere se...

The Y chromosome is important for male development as it contains the sex determining gene SRY and many spermatogenesis genes. Structural abnormalities of the Y chromosome include rings, deletions, inversions, and dicentrics. 4 These types of abnormalities are common in infertile males (1.5%), especially those with azoospermia. 6 However, such rearrangements are unstable and an additional 45,X ...

The Y chromosome is important for male development as it contains the sex determining gene SRY and many spermatogenesis genes. Structural abnormalities of the Y chromosome include rings, deletions, inversions, and dicentrics. 4 These types of abnormalities are common in infertile males (1.5%), especially those with azoospermia. 6 However, such rearrangements are unstable and an additional 45,X ...

Fluorescence in situ hybridization (FISH) has become a powerful tool in chromosome analysis. This report describes the systematic optimization of the Fast-FISH technique for centromere labeling of human metaphase chromosomes for radiobiological dosimetry purposes. For the present study, the hybridization conditions and the efficiency of two commercially available alpha-satellite DNA probes were...

An account is given of the cytogenetic investigations of a girl with Down's syndrome found to have a dicentric duplication of chromosome 21. This tandem type of rearrangement was interpreted as a recombinant derived from a single meiotic crossover between a maternal ring 21 and its normal homologue. A population of cells was also found in which breakage of the dicentric resulted in a chromosome...

Many human malignant tumours exhibit abnormal chromosomal segregation at cell division. It is believed that these anomalies play a role in tumorigenesis by increasing the rate of chromosome mutations, including deletion and amplification of genes involved in cellular proliferation and/or survival. In vitro experiments have also shown that mitotic instability may be a mechanism for developing re...

Centromeres and telomeres assure stability of eukaryotic chromosomes that undergo multiple segregations during cell divisions (Blackburn and Szostak, 1984). Chromosome movement during mitosis and meiosis is regulated by a centromere, which exists in each chromosome. The protein complex assembled at each centromere, named the kinetochore, serves as an attachment site for spindle microtubules (Cl...