Association studies aim to find patterns among 0.1% variation in the human genome (mostly represented by SNPs) corresponding to differences in complex pheno-types such as disease susceptibility and response to drugs. The success of such studies relies on accuracy, sensitivity, and high throughput in SNP genotyping. Many of the technologies described in this article are geared toward highly parallel analysis, although MS stands out as a platform where increased throughput is realized by ultrarapid serial processing.

The sensitivity of most genotyping techniques reflects some form of amplification step either before, during, or after the actual allele discrimination assay. In the majority of cases, this amplification step relies on the PCR, but novel formats such as the Invader assay and RCAT are also becoming popular. Although homogenous assay formats are versatile, array-based technology platforms have the advantage of higher throughput. Recent develop-ments[4] include the use of electrostringent hybridization arrays, where electric currents are used to increase the speed and sensitivity of hybridization, and the detection of allele-specific products based on their electrochemical properties when hybridized to oligonucleotide probes attached to minute electrodes. Another emerging technology, bead arrays, combines the flexibility of the homogenous assay format with the convenience and throughput of chip-based detection systems. Bead array systems that employ fluorescence-based detection and sorting are commercially available from Lynx Therapeutics and Illumina, Inc.


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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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