As far as the authors are aware this is the first report of the insertion of an active NOR into a non-acrocentric chromosome, although a simple translocation involving an active NOR has been previously recorded. More specifically, this case involves the non-reciprocal translocation of the centromere and stalk of an acrocentric into 12p, generating an apparently stable dicentric chromosome. The ...

Loss of telomeric DNA during cell proliferation may play a role in ageing and cancer. Since telomeres permit complete replication of eukaryotic chromosomes and protect their ends from recombination, we have measured telomere length, telomerase activity and chromosome rearrangements in human cells before and after transformation with SV40 or Ad5. In all mortal populations, telomeres shortened by...

The dose from ionizing radiation exposure can be interpolated from a calibration curve fit to the frequency of dicentric chromosomes (DCs) at multiple doses. As DC counts are manually determined, there is an acute need for accurate, fully automated biodosimetry calibration curve generation and analysis of exposed samples. Software, the Automated Dicentric Chromosome Identifier (ADCI), is presen...

COMPARISON of microsporogenesis and microspore development A in a triploid Tradescantia has shown significant deviations from the normal diploid behavior. Occasional dicentric chromatids a t meiosis are found in diploid Tradescantias, but inversion crossovers in the triploid are much more frequent. An analysis of microspore development in a triploid Tradescantia shows that chromosome number has...

second gamete. In each case, the broken end of the second chromosome 9 had no unsaturated end with which it could unite. As expected, this single broken end thereafter healed. Conclusions.-The experiments outlined allow some specific answers to be given to the questions presented in the first paragraph of this paper. Question (1) may be answered in the negative. Two chromosomes do not have to b...

Amplification of large genomic regions associated with complex translocations (complicons) is a basis for tumor progression and drug resistance. We show that pro-B lymphomas in mice deficient for both p53 and nonhomologous end-joining (NHEJ) contain complicons that coamplify c-myc (chromosome 15) and IgH (chromosome 12) sequences. While all carry a translocated (12;15) chromosome, coamplified s...

Y chromosome microdeletions are the second genetic cause of male infertility. The incidence of Y chromosome microdeletions can vary considerably depending on several factors, including patient selection criteria, population composition, and diagnostic protocols. They are associated with spermatogenic failure and lead to azoospermia or oligozoospermia. The advance in assisted reproductive techno...

Investigations into the biophysical properties of single molecules traditionally involve well defined in vitro systems where parameters such as solvent viscosity and applied forces are known a priori. These systems provide means to develop models describing the polymers response to a variety of conditions, including the entropically driven relaxation of a stretched biopolymer upon release of th...