the most significant complication of pregnancy is recurrent miscarriage. numerous factors have been described as associations with recurrent wastage such as: uterine abnormalities, immunological factors, endocrinologic imbalance and chromosomal defects. cytogenetic evaluation of couples with recurrent pregnancy losses is performed on the basis of g-banding technique only after other possible et...

A likely mechanism of chromosomal rearrangement formation involves joining the ends from two different chromosomal double-strand breaks (DSBs). These events could potentially be mediated by either of two end-joining (EJ) repair pathways [canonical nonhomologous end joining (C-NHEJ) or alternative end joining (ALT-EJ)], which cause distinct rearrangement junction patterns. The relative role of t...

A RecA-independent chromosomal rearrangement in the upstream region of the streptolysin O (slo) gene of Streptococcus pyogenes which affects slo expression was identified. PCR analysis was used to demonstrate that this kind of rearrangement was found in several strains of different lineages. Chromosomal loci involved in the recombination were found to be 746 kb apart on the 1.85-Mb-long chromos...

T cell receptor (TCR) and variable region genes are assembled from germ-line gene segments located in a single chromosomal locus in which TCR segments are situated between TCR segments. The TCR enhancer (E ) located at the 3 end of the TCR locus functions over a long chromosomal distance to promote TCR rearrangement and maximal TCR expression; whereas the TCR enhancer (E ) is located among the ...

The Streptomyces glaucescens genome frequently undergoes gross genomic rearrangement events which result in the deletion of extremely large segments of chromosomal DNA. The structure and origin of the DNA forming the novel junctions arising from five of these deletion events are described. Only one junction proved to be the result of a relatively simple event; the remainder were more complex, w...

In order to apply gene-order rearrangement algorithms to the comparison of genome sequences, Pevzner and Tesler bypass gene finding and ortholog identification and use the order of homologous blocks of unannotated sequence as input. The method excludes blocks shorter than a threshold length. Here we investigate possible biases introduced by eliminating short blocks, focusing on the notion of br...

Recent results indicate that the rate of chromosomal rearrangement in the genus Drosophila is the highest found so far in any eukaryote. This conclusion is based chiefly on the comparative mapping analysis of a single chromosomal element (Muller's element E) in two species, D. melanogaster and D. repleta, representing the two farthest lineages within the genus (the Sophophora and Drosophila sub...