"A Single Nucleotide Polymorphism, or SNP is a single base, point, genetic change, or variation, that can occur within a person's DNA sequence. The genetic code is specified by the four nucleotide "letters" A (adenine), C (cytosine), T (thymine), and G (guanine). SNP variation occurs when a single nucleotide, such as an A, replaces one of the other three nucleotide letters - C, G, or T" 1. Specifically, the apparent benign genetic change represents a deviation from the "normal" or known, common sequence for a particular gene.

SNPs that appear in the promoter region, coding region, or at exon/intron boundaries may result in altered transcriptional regulation, altered amino acid sequence in the gene product, and altered mRNA editing (splicing), respectively. Investigating the frequency and phenotypic correlates with known SNPs harbors the potential to discover specific genes that are responsible for predisposition for disease risk, as well as offers value in forensics research and population genetics. Many efforts to use SNP's for understanding genetic variability are now ongoing. High Throughput laboratories are undergoing research to map SNP's for disease diagnosis, pharmacogenomics , and agricultural genetics. Several institutions have exceeded runs of 100,000,000 wells per year. Given the increasing focus on SNP technology, there is an immediate need to increase throughput using robotic automation and to reduce reagent costs with nanoliter dispensing.

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