A A C Snp1 Snp2 Snp3

Fig. 2 The differences between molecular haplotyping and genotyping methods are exemplified and illustrated in this graph. The main difference is the use of dilutions of genomic DNA down to a level where statistically only one molecule is present in the sample.

2. Primers for the MassEXTEND® reaction must be designed so the combination of expected peak masses are resolvable for unambiguous genotyping. For the MassEXTEND® primer design there are two choices available as either site adjacent to the SNP can be used. The following should be considered: 1) optimal length (17-24 mer); 2) primers may not contain uncertain bases in the target sequence; 3) primers with low Tm should be disregarded because of hairpin formation, false priming, and primer-dimer potential; 4) problematic sequence repeats such as GGGG should be avoided; and 5) potential mass conflicts with by-products (e.g., depurination products and possible extend-pausing products) need to be avoided. For example, a MassEXTEND® primer prematurely terminated with dA would have exactly the same mass as if normally terminated with ddG.

A 12- to 15-fold multiplex assay can be routinely carried out and 20-30-fold plexing levels may be achievable with assay optimization. The 15-fold multiplexing with ~ 1 hr acquisition/real-time analysis of 384 elements translates into an analytical speed of ~ 100 genotypes per minute (or 5760 genotypes/hr). This throughput coupled with a cost/genotype of currently below 100 renders whole-genome scans studies feasible and affordable.

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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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