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PCR Protocol
DNA Measurement Protocol
Research and Development
Background on Disease Markers
Cystic fibrosis is a disease that can be passed on down genetically along the familial line. The disease causes a build up of thick mucus on the inside of the lungs, digestive tract and other parts of the body. Cystic Fibrosis is the most common chronic lung disease to effect children and young adults and is usually diagnosed by the age of two; however, there are weaker strains of the disease that often go un-diagnosed until the age of 18 or later. The disease is recessive so to suffer the disease one must have the gene from both parents. The disease is life-threatening, the mucus builds up and can eventually suffocate the victim. Around 1 in 29 Caucasians of middle European dissent suffer from cystic fibrosis, this is the most susceptible group to this disease.
One such SNP which signals for a susceptibility to Cystic Fibrosis is the [A/G] swap changing the codon from TGG ⇒ TGA. This change has been recorded in two patients suffering from cystic fibrosis the swap occurs at nucleotide 302 in exon 3 converting codon 57 from TGG (trp) to TGA (stop).
More information can be found: http://www.ncbi.nlm.nih.gov/projects/SNP/snp_ref.cgi?rs=121909025
Primer Design
The primers must be built around the sequence CGTCTCTAC[T/C]CTATCTCTC with the thymine swapped for the cytosine giving the primers:
Reverse primer: 3' CGTCTCTTACTCTATCTCTC 5'
Forward primer: 5' AAATATCTGGCTGAGTGTTT 3'
These primers are 150 bp apart so as to allow the PCR reaction to occur faster, shortening the 30 seconds required per temperature cycled to 10 seconds per cycle.
Illustration
Forward and reverse primers binding to the SNP signaling Cystic Fibrosis.
<http://openwetware.org/images/1/1f/Acetic_acid_db.jpeg>
Image credit to www.nature.com
Pray, Leslie A., Ph.D. "The Biotechnology Revolution: PCR and the Use of Reverse Transcriptase to Clone Expressed Genes." Nature.com. Nature Publishing Group, 2008. Web. 15 Nov. 2012.
General PCR is very similar to our new version of PCR. The only difference is that our primers are only fifteen base pairs long and will be only 150 base pairs apart. So each copied segment in this illustration is 150 base pairs long and the primers look like the first illustration.
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