Polymerase chain reaction amplification of a GC rich region by adding 1,2 propanediol


1 Isfahan Clinical Toxicology Research Center, Isfahan University of Medical Sciences, Isfahan, Iran

2 Department of Pharmaceutical Biotechnology, Isfahan University of Medical Sciences, Isfahan, Iran


Background : Apolipoprotein E (ApoE) is one of the most important carriers of lipids in mammalians. The gene for this lipoprotein (ApoE) is located on chromosome 19 which is related with the pathogenesis of some nervous system disease. ApoE gene is identified as a high guanine-cytosine (GC) content fragment. Detection and amplification of these templates are extensively laborious and baffling. The aim of this study was to find a practical and feasible method for the amplification of the number of GC rich genes such as ApoE.
Materials and Methods: We experimented with simple polymerase chain reaction (PCR), nested PCR and PCR with 1-2 propanediol, dimethylsulfoxide (DMSO), and ethyleneglicol as additive substances to enhance the amplification ApoE gene and used the 40 samples of the human whole blood were collected in test tubes with a pre-treatment of ethylene diaminetetraacetic acid.
Results: According to our observations, presence of 1-2 propanediol, DMSO, and ethyleneglicol as additive substances resulted to enhanced amplification of ApoE gene. Addition of 1-2 propanediol showed the best results, caused optimization and revealed more specific and sharp bands.
Conclusion: According to our findings 1-2 propanediol are the best organic reagent for improving the amplification of ApoE gene. Optimization procedure for each GC rich sequence is recommended to be performed separately in order to identify which of the additive agent is more efficient and applicable for a particular target.


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