Future of Engineering
Sunday, April 6, 2008
Quencher-free Molecular Beacons Mean Better Fluorescent Techniques for DNA Analysis
B. H. Kim, Y. J. Seo and N. Venkatesan at Pohang University of Science and Technology in Korea explain why quencher-free molecular beacons mean a brighter outlook for medicine.
Genetic analysis underpins DNA diagnostics. Swapping just a couple of letters in an individual's genome can cause an incurable genetic disorder, so identifying genetic differences is very important to diagnose and possibly cure certain diseases.
"When the target DNA is added, the hairpin opens out to bind to the DNA and the fluorophore is no longer quenched. So the target DNA is detected by an increase in fluorescence. "Unravelling the 'secret of life' by completing sequencing of the human genome, has led to our better understanding of genetic differences, be it between individuals, between parents and their offspring or normal and abnormal genes in genetic disorders. Such differences are expressed in terms of single nucleotide polymorphisms (SNPs, a single base change in a DNA sequence) or copy number variations (CNVs, when the number of copies of a gene varies).
Initially, DNA analysis relied mainly on radiolabelled nucleotides. Now fluorescent techniques are being used increasingly. Analytical methods that use fluorescent probes to bind to particular DNA regions are now well-known. So-called molecular beacons (MBs), these probes are now being used during DNA amplification by polymerase chain reactions (PCR), to qualitatively as well as quantitatively estimate single or multiple gene sequences simultaneously. Similarly, different types of MBs are used in related applications such as protein analysis and to study protein-DNA interactions. In addition, MBs' suitability for probing the levels and kinetics of DNA photodamage, and as vehicles for photoinduced drug release has also been explored.
More from here
Genetic analysis underpins DNA diagnostics. Swapping just a couple of letters in an individual's genome can cause an incurable genetic disorder, so identifying genetic differences is very important to diagnose and possibly cure certain diseases.
"When the target DNA is added, the hairpin opens out to bind to the DNA and the fluorophore is no longer quenched. So the target DNA is detected by an increase in fluorescence. "Unravelling the 'secret of life' by completing sequencing of the human genome, has led to our better understanding of genetic differences, be it between individuals, between parents and their offspring or normal and abnormal genes in genetic disorders. Such differences are expressed in terms of single nucleotide polymorphisms (SNPs, a single base change in a DNA sequence) or copy number variations (CNVs, when the number of copies of a gene varies).
Initially, DNA analysis relied mainly on radiolabelled nucleotides. Now fluorescent techniques are being used increasingly. Analytical methods that use fluorescent probes to bind to particular DNA regions are now well-known. So-called molecular beacons (MBs), these probes are now being used during DNA amplification by polymerase chain reactions (PCR), to qualitatively as well as quantitatively estimate single or multiple gene sequences simultaneously. Similarly, different types of MBs are used in related applications such as protein analysis and to study protein-DNA interactions. In addition, MBs' suitability for probing the levels and kinetics of DNA photodamage, and as vehicles for photoinduced drug release has also been explored.
More from here
Labels: Bio-engineering
PermaLink - Quencher-free Molecular Beacons Mean Better Fluorescent Techniques for DNA Analysis posted by Ecacofonix : 9:23 PM
