Comparative genomic hybridization and its application to Wilms' tumorigenesis.

Eighty sporadic Wilms' tumor samples were analyzed by comparative genomic hybridization (CGH) to identify chromosomal regions involved in the etiology of the disease. Twenty percent of the samples showed chromosomal gains or losses. The majority of chromosomal gains and losses were similar to those identified through molecular and cytogenetic studies.

Frequent loss of chromosome 14 in atypical and malignant meningioma: identification of a putative 'tumor progression' locus.

Formation of meningiomas has been associated with the loss of genetic material on chromosome 22. To approach the additional chromosomal events that underlie progression of these tumors to malignancy, we have examined several other chromosomal regions for loss of heterozygosity (LOH) in these tumors. Fifty-eight tumors, comprising 43 benign meningiomas, 11 atypical meningiomas and four malignant meningiomas, were examined.

Identification of highly conserved loci by genome painting.

Fluorescence in situ hybridization was used to identify patterns of DNA similarity among the genomes of several rodent taxa. Total genomic or Cot-1 DNAs were used as hybridization probes against metaphase preparations across different taxonomic levels, including three species of Microtus (suborder Sciurognathi), three species of Microtus (suborder Sciurognathi), Mus musculus (suborder Sciurognathi) and Ctenomys steinbachi (suborder Hystricognathi). The hybridization patterns of Mus or Peromyscus (sciurognath) DNA to Mus metaphases, which were consistent with what is known of the satellite sequences in these species, demonstrated the efficacy of this approach for molecular cytogenetics and evolutionary biology.

Physical mapping of the uterine leiomyoma t(12;14)(q13-15;q24.1) breakpoint on chromosome 14 between SPTB and D14S77.

Uterine leiomyoma is the most common tumor of smooth muscle cell origin and is often associated with the recurrent balanced translocation t(12;14)(q13-15;q24). As an initial step toward finding the gene or genes that are interrupted by the translocation breakpoint, a somatic cell hybrid carrying the derivative 14 as the single t(12;14) translocated chromosome was constructed from a leiomyoma cell line with this translocation. Sequence tagged sites (STS) whose locations on the genetic map of chromosome 14 were known were used to map the breakpoint in the translocated chromosomes.

Molecular cloning and physical and genetic mapping of the human anion exchanger isoform 3 (SLC2C) gene to chromosome 2q36.

A human clone corresponding to the gene encoding anion exchanger isoform 3 (AE3) (approved gene symbol SLC2C) has been isolated and partially sequenced. Oligonucleotide primers based on this sequence were used in a polymerase chain reaction to specifically amplify a segment of the human gene from a panel of human-rodent somatic cell hybrids, allowing the assignment of AE3 to chromosome 2. To map AE3 more precisely to a cytogenetic band on chromosome 2, the AE3 cosmid was used as a probe in fluorescence in situ hybridization to human metaphase chromosomes.

High resolution mapping of overlapping cosmids by fluorescence in situ hybridization.

The constituents of two cosmid contigs were analyzed by high resolution mapping using two-color fluorescence in situ hybridization (FISH) to extended DNA molecules. Samples were prepared by lysing the nuclei in situ followed by histone depletion. This treatment results in elongate DNA filaments appropriate for high resolution mapping.

Narrowing the position of the Treacher Collins syndrome locus to a small interval between three new microsatellite markers at 5q32-33.1.

Treacher Collins syndrome (TCOF1) is an autosomal dominant disorder of craniofacial development, the features of which include conductive hearing loss and cleft palate. The TCOF1 locus has been localized to chromosome 5q32-33.2.

Detection of fetal cells with 47,XY,+21 karyotype in maternal peripheral blood.

Fetal cells were isolated from the peripheral blood of a pregnant woman at 19 weeks of gestation whose fetus had Down syndrome. An amniocentesis had been performed 2 weeks earlier because of abnormalities detected on an antenatal sonogram. Fetal cells were separated by fluorescence-activated cell sorting using monoclonal antibody to the transferrin receptor (TfR).

Rapid detection of chromosome aneuploidies in uncultured amniocytes by using fluorescence in situ hybridization (FISH).

Herein we report the results of the first major prospective study directly comparing aneuploidy detection by fluorescence in situ hybridization of interphase nuclei with the results obtained by cytogenetic analysis. We constructed probes derived from specific subregions of human chromosomes 21, 18, 13, X, and Y that give a single copy-like signal when used in conjunction with suppression hybridization. A total of 526 independent amniotic fluid samples were analyzed in a blind fashion.

Fluorescence microscopy of the dynamics of supercoiling, folding, and condensation of bacterial chromosomes, induced by acridine orange.

The fluorescent dye, acridine orange, was used to visualize bacterial chromosomes extending from bacteria attached to a glass surface. The acridine-induced condensation of these chromosomes was followed in real-time with a low light level video camera. Acridine orange induced the packing of the bacterial chromosome into thick bundles which underwent various forms of condensation, supercoiling, folding, and rolling into a compact particle.

Real-time imaging of single DNA molecules with fluorescence microscopy.

A fluorescence microscopy technique was used to image the dynamics of individual DNA molecules. Lambda, calf thymus, cosmid (circular), and T4 DNA were studied with the fluorescent dye acridine orange. Experiments with DNAase I were conducted, and the results indicate that these observations correspond to DNA molecules.