Polymerase chain reaction flanking sequences

It should be emphasized that the polymerase chain reaction requires specific primers for synthesis therefore, the sequence flanking the sequence to be amplified must be known. PCR reactions are also very susceptible to contamination by other DNA. Precautions against contamination need to be... 

Steps in the polymerase chain reaction (PCR). The DNA to be amplified is denatured and annealed with two oligonucleotides that flank the region of interest. These oligonucleotides (or primers) are extended. Extension continues to the ends of the DNA strands. The products are again denatured and annealed to primers for a second round of extension. This process of denaturation, annealing, and primer extension is repeated many times. The primary product of the reaction is duplex DNA, bounded by the sequences of the primers. (From J. L. 

The polymerase chain reaction is a methodology that is very well suited for the analysis of chromosomal translocations, particularly when the translocation breakpoints are clustered and the sequences flanking the translocation breakpoints are well characterized. 

Short tandem repeat (STR) or microsatellite loci consist of DNA sequence motifs that have core repeats of two to seven base pairs. Examples include the dinucleotide 5 CACACACA 3 and the tetranucleotide 5 TTTATTTATTTA 3". Thousands of STRs are scattered throughout the genome. Because they are flanked by unique sequences, each can be specifically amplified with the polymerase chain reaction (PGR) for analysis. In populations of individuals, multiple alleles may be present based on differences in the number of repeated motifs at the locus. STRs have many characteristics that make them ideal for identity testing (1) They can be analyzed in fluorescent automated systems (2) alleles can be assigned in a definitive manner following analysis (3) STR loci are almost always transmitted in families in a Mendelian fashion (4) the loci may have 10 or more alleles, often with... 

The polymerase chain reaction (PCR) permits exponential amplification of a specific segment of DNA from just a single initial template DNA molecule if the sequence flanking the DNA region to be amplified is known (see Figure 9-24). 

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