Dna Sequencing

Pyrosequencing can be used as an alternative to the traditional Sanger dideoxy sequencing method. The sequencing assay is performed by a reiteration of steps in which one of the four nucleotides is added and tested sequentially for incorporation into the nascent nucleotide chain. When the nucleotide added is complementary to the DNA template, it incorporates into the DNA strand and a light signal is generated. The intensity of the light signal reflects the number of incorporated nucleotides in a single nucleotide repeat region. Compared to the Sanger sequencing method, the pyrosequencing technique is limited to read up to 100 nucleotides.1-7-1 However, the pyrosequencing technique has several unique advantages over Sanger sequencing. For example, the results of heterozygous genotypes or multiplexing assays by Sanger dideoxy sequencing show overlapping signal peaks in a single position, which may result in sequence misreading. Conversely, pyrosequencing obtains sequencing data from each allele independently, which allows it to simultaneously sequence multiplex loci of a gene family.[8] Additionally, pyrosequencing is able to capture the first base following the sequencing primer.

Pyrosequencing DNA sequencing is being used for a wide variety of disciplines.1-9,10-1 Pyrosequencing has been employed to obtain 50-100-bp sequence data in the variable region of the 16S rRNA using PCR primers based on the conservative region for amplification. This sequencing assay allows for the rapid identification of bacteria.[11] Similarly, the pyrosequencing technique has been applied for yeast and virus typing, and mutation testing.[12,13]

The pyrosequencing assay is also used for human leukocyte antigen (HLA) genotyping, which is essential for matching the HLAs of a recipient and an unrelated donor to decrease graft rejection and transplant-related mortality. The genetic complexity of HLA genes results in extreme difficulty in genotyping the donor and recipient HLA haplotypes by traditional methods. Sequence-based genotyping is necessary because it provides critical information for HLA matches considering that histocom-patibility between recipient and donor is inversely correlated with the number of mismatches. The high-throughput pyrosequencing technique can be used to obtain high-resolution sequencing information of HLA genotyping that overcomes these problems.[8,14]

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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