AZF deletions are genomic deletions in the euchromatic part of the long arm of the human Y chromosome (Yq11) associated with azoospermia or severe oligozoospermia. Consequently, it can be assumed that these deletions remove Y chromosomal genes required for spermatogenesis. However, these 'classical' or 'complete' AZF deletions, AZFa, AZFb and AZFc, represent only a subset of rearrangements in Y...

A filamentous soil bacterium, Streptomyces griseus 2247, carries a 7. 8-Mb linear chromosome. We previously showed by macrorestriction analysis that mutagenic treatments easily caused deletions at both ends of its linear chromosome and changed the chromosome to a circular form. In this study, we confirmed chromosomal circularization by cloning and sequencing the junction fragments from two dele...

Chromosomal translocation is one mechanism by which cellular oncogenes may be activated during tumorigenesis. The translocation of the abl oncogene to the Philadelphia chromosome in chronic myelogenous leukemia (CML) results in a new RNA transcript that fuses sequence from chromosome 22 to sequence from the abl oncogene. This RNA presumably codes for a new abl-related protein product found in C...

Genetic crosses in many organisms have shown that alleles of unlinked genes generally assort independently of one another during gamete formation. However, variation in chromosome size may affect the process of meiosis and lead to nonindependent assortment of chromosomes. We therefore examined chromosomes with insertions and found that they preferentially segregated away from the X chromosome d...

Partial deletion of the long arm of chromosome 7 is a common abnormality in the bone marrow cells of patients with myelodysplastic syndrome (MDS) or acute nonlymphocytic leukemia (ANLL). This study was undertaken to characterize the chromosome breakpoints in molecular terms and to determine if hemizygosity or submicroscopic deletions occur in patients without any cytogenetically detectable abno...

Recent evidence indicates that the mutation of retinoblastoma suscep tibility (RB) gene is also involved in the development of osteosarcoma. We studied 30 cases of osteosarcoma for the structural anomalies of the RB gene by Southern hybridization analysis with cDNA probes of the RB gene. Thirteen cases (43%) showed structural anomalies of the RB gene. They included the total or partial deletion...

Certain configurations of maize Ac/Ds transposon termini can undergo alternative transposition reactions leading to chromosome breakage and various types of stable chromosome rearrangements. Here, we show that a particular allele of the maize p1 gene containing an intact Ac element and a nearby terminally deleted Ac element (fAc) can undergo sister-chromatid transposition (SCT) reactions that g...

The recent publication of the complete sequence of human chromosome 22 provides a platform from which to investigate genomic sequence variation. We report the identification and characterization of 12,267 potential variants (SNPs and other small insertions/deletions) of human chromosome 22, discovered in the overlaps of 460 clones used for the chromosome sequencing. We found, on average, 1 pote...

Cloned DNA probes were used in combination with a panel of five hybrid cell clones containing a series of different terminal deletions in human chromosome 11 to map precisely the human hemoglobin beta and delta chain structural genes contained on this chromosome. The region of deletion in each clone of the panel has been defined by biochemical, immunologic, and cytogenetic markers. DNA from clo...

Note Chromosomal deletions are among the most common genetic events observed in hematologic malignancies; loss of genetic materiel is regarded as a hallmark of putative tumor suppressor gene localization. Deletions 13q occurs in lymphoid neoplasias: see del(13q) in non-Hodgkin's lymphoma and del(13q) in chronic lymphoproliferative diseases. In myeloid disorders, the most frequently reported del...