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Sensitive and accurate measurement of photoproducts induced in DNA by natural or artificial ultraviolet-B (UVB; and UVC) light is essential to evaluate the toxic and mutagenic effects of this radiation. Monoclonal antibodies specific for the two major classes of photoproducts—cyc ...

Single-cell gel electrophoresis (SCGE) or the comet assay is a powerful tool for the detection of DNA single- and double-strand breaks and base damage and for investigating the kinetics of DNA strand break rejoining in human and animal model systems. It is a versatile technique that can be applied in ...

The comet-FISH technique described in this protocol is a tool to detect genome region-specific DNA damage and repair. It is a combination of two established techniques, the comet assay (or single-cell gel electrophoresis, or the single-cell gel test), to separate highly fragmented from mod ...

This paper describes a unique, simple, and rapid method for inducing premature chromosome condensation (PCC) in “resting” human peripheral blood lymphocytes (HPBLs) and also explains an approach to studying numerical changes and/or structural aberrations involving specific c ...

Risk assessment is now recognized as a multidisciplinary process, extending beyond the scope of traditional epidemiologic methodology to include biological evaluation of interindividual differences in carcinogenic susceptibility. Modulation of environmental exp ...

The in vivo micronucleus (MN) test in bone marrow or peripheral blood erythrocytes is widely used as a short-term assay for the detection of agents able to induce chromosome aberrations in somatic cells and has also been shown to have good predictive potential for the identification of carcinog ...

The comet assay or single-cell gel (SCG) test is a microgel electrophoresis technique that measures DNA damage at the level of single cells. A small number of cells suspended in a thin agarose gel on a microscope slide is lysed, electrophoresed, and stained with a fluorescent DNA binding dye. Cells with ...

Determining mutant frequencies in endogenous reporter genes is a tool for identifying potentially genotoxic environmental agents and discovering phenotypes prone to genomic instability and diseases, such as cancer. Here we describe a high-throughput method for identifying ...

This chapter describes the use of the bacteriophage cII positive selection assay with the Muta™Mouse transgenic model system. The assay is similar to others involving a transgenic target, including the cII and lacI assays in the Big Blue� Mouse, lacZ in the MutaMouse, and the gpt delta assay. Brief ...

The T-cell cloning assay, which detects mutations in the gene for hypoxanthine-guanine phosphoribosyltransferase (HPRT), is the most well-developed reporter system for studying specific locus mutation in human somatic cells. The assay is based on a mitogen- and growth factor-depe ...

The HPRT assay uses incorporation of toxic nucleotide analogs to select for cells lacking the purine scavenger enzyme hypoxanthine-guanine phosporibosyltransferase. A major advantage of this assay is the ability to isolate mutant cells and determine the molecular basis for their f ...

Specific recurring chromosomal translocations and deletions are found in a variety of cancers. In hematopoietic malignancies, many of these chromosomal aberrations result from mistakes involving V(D)J recombination. V(D)J recombination is required for the formation of func ...

The glycophorin A (GPA) assay concurrently detects and quantifies two types of erythrocytes with variant phenotypes at the autosomal locus responsible for the polymorphic MN blood group. It uses a pair of allele-specific monoclonal antibodies and flow cytometry to analyze a standard p ...

A protocol for detection of mutations in the TP53 gene using temporal temperature gradient gel electrophoresis (TTGE) is described. TTGE is a mutation detection technique that separates DNA fragments differing by single base pairs according to their melting properties in a denaturing ...

Spontaneously generated mutant T cells defective in T-cell receptor (TCR) gene expression are detectable at the frequency of 10−4 in vivo, and the mutant fractions are dose-dependently increased by exposure to genotoxic substances such as ionizing radiation. Mutant cells with altered ...

Mutations in the P53 tumor suppressor gene and the K-RAS oncogene have frequently been found in sputum and bronchoalveolar lavage (BAL) samples of lung cancer patients, and also in samples from patients prior to presenting clinical symptoms of lung cancer, suggesting they may provide useful ...

Methods that detect rare base substitutions within populations of DNA molecules are valuable tools for studying the DNA-damaging effects of chemicals and for pool screening for single-nucleotide polymorphisms. Allele-specific competitive blocker-polymerase chain rea ...

Single-strand conformation polymorphism (SSCP) for screening mutations/single-nucleotide polymorphisms (SNPs) is a simple, cost-effective technique, saving an expensive exercise of sequencing each and every PCR reaction product and assisting in choosing only the ampli ...

Although it has been more than 20 yr since its discovery, the ras family of genes has not yet lost its impact on basic and clinical oncology. These genes remain central to the field of molecular oncology as tools for investigating carcinogenesis and oncogenic signaling, as powerful biomarkers for t ...

The DNA mismatch repair (MMR) pathway plays a prominent role in the correction of errors made during DNA replication and genetic recombination and in the repair of small deletions and loops in DNA. Mismatched nucleotides can occur by replication error, damage to nucleotide precursors, dama ...