BACKGROUND Apolipoprotein E (apoE) is found in association with triglyceride-rich lipoproteins and is the ligand for the removal of these particles from the plasma. Genetic variations in exon 4 lead to three common gene variants: E2, E3, and E4. METHODS We performed apoE genotyping in 765 individuals with type 2 diabetes. RESULTS We identified three new variant heteroduplex patterns. Sequen...

The genomes of temperate Salmonella typhimurium phages P22 and L share approximately 69% homology, as measured by DNA heteroduplex analysis. Alignment of the P22/L heteroduplex molecules with a P22 physical map places most of this homology between the capsid genes and genes in the vicinity of the prophage attachment sites. The degree of genetic relatedness between these phages and the lambdoid ...

We have used R-loop formation and direct hybridization techniques to analyze the kinetics by which RNA is displaced from a heteroduplex by DNA of identical sequence. Using random walk simulations we were able to calculate the step times for a single displacement reaction. For RNA with a GC content of 57-60% the data indicate an RNA exchange probability of 50.06%, which is indicative of a modest...

The possibility to detect markers of T-cell clonality at the T-cell receptor (TCR) beta and gamma loci in skin biopsy samples has proven to be helpful for the often difficult clinical and immunohistochemical diagnosis of cutaneous T-cell lymphoma (CTCL). However, particularly at the early stage of the neoplastic infiltration, an emerging clonal pattern at Southern may be obscured by the germlin...

Herein, using DNA adenine methylation (Dam) methyltransferase (MTase) as a model analyte, a novel fluorescence sensing strategy was developed for facile, rapid and highly sensitive detection of the activity and inhibition of the target based on methylation-blocked enzymatic recycling amplification. In this sensing system, nicking endonuclease Nt.AlwI with the methylation-sensitive property was ...

The MutS DNA mismatch protein recognizes heteroduplex DNAs containing mispaired or unpaired bases. We have examined the oligomerization of a MutS protein from Thermus aquaticus that binds to heteroduplex DNAs at elevated temperatures. Analytical gel filtration, cross-linking of MutS protein with disuccinimidyl suberate, light scattering, and matrix-assisted laser desorption/ionization time-of-f...

Preparation of heteroduplexes in large quantities with high purity is essential for the measurement of DNA mismatch repair (MMR) activity. Here we report a rapid, less labor-intensive method for the preparation of a heteroduplex plasmid that expresses the enhanced green fluorescent protein (EGFP) if the mismatch is repaired correctly. The method involves the use of a wild-type and a mutated EGF...

Unitary models of meiotic recombination postulate that a central intermediate containing Holliday junctions is resolved to generate either noncrossover or crossover recombinants, both of which contain heteroduplex DNA. Contrary to this expectation, we find that during meiosis in Saccharomyces cerevisiae, noncrossover heteroduplex products are formed at the same time as Holliday junction interme...

Crossover and noncrossover recombinants can form by two different pathways during meiotic recombination in Saccharomyces cerevisiae. The MER3 gene is known to affect selectively crossover, but not noncrossover, recombination. The Mer3 protein is a DNA helicase that unwinds duplex DNA in the 3' to 5' direction. To define the underlying molecular steps of meiotic recombination, we investigated th...