Direct fluorescence detection

The most straightforward way to detect an allele-specific product is to label it by incorporating one or more nucleotides conjugated to a fluorescent dye. Direct fluorescence detection is generally used with solid-phase assay formats (microarrays and bead arrays) and where allele-specific products are separated by gel electropho-resis or capillary electrophoresis.

A variation on this approach is to use an intercalating fluorescent dye such as ethidium bromide and to study the melting profile of DNA duplexes. This method for typing SNPs is known as dynamic allele-specific hybridization (DASH).[11] One (unlabeled) ASO is added to a PCR product and allowed to anneal in the presence of an intercalating dye, which fluoresces specifically in the presence of double-stranded DNA. The reaction is then heated, and fluorescence is measured in real time as the temperature rises. As the duplex denatures, fluorescence steadily decreases. When the melting temperature of the probe is reached, denaturation is completed and the fluorescent signal falls to background levels. The thermal melting profile of each allele is different because one is perfectly complementary to the probe and the other contains a mismatch.

Getting Started With Dumbbells

Getting Started With Dumbbells

The use of dumbbells gives you a much more comprehensive strengthening effect because the workout engages your stabilizer muscles, in addition to the muscle you may be pin-pointing. Without all of the belts and artificial stabilizers of a machine, you also engage your core muscles, which are your body's natural stabilizers.

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