Chemistry Reference and  Research
           
 
Periodic Table
- standard table
- large table
 
Chemical Elements
- by name
- by symbol
- by atomic number
 
Chemical Properties
 
Chemical Reactions
 
Organic Chemistry
 
Branches of Chemistry
Analytical chemistry
Biochemistry
Computational Chemistry
Electrochemistry
Environmental chemistry
Geochemistry
Inorganic chemistry
Materials science
Medicinal chemistry
Nuclear chemistry
Organic chemistry
Pharmacology
Physical chemistry
Polymer chemistry
Supramolecular Chemistry
Thermochemistry

Helicase-dependent amplification

Helicase-dependent amplification (HDA) is a method for in vitro DNA amplification like the polymerase chain reaction.

The disadvantage of PCR is that it consumes a lot of time with uncoiling the double-stranded DNA with heat into single strands (a proces called denaturation) and copying the single strands to create new double-stranded DNA (synthesis). Instead of these thermocycles, HDA mimics nature’s method of replicating DNA by using helicase (an enzyme) to denature the DNA at a constant temperature of 37°C.

The advantages of HDA over PCR are increased speed, reduced costs and the prospect of creating a hand-held DNA diagnostic device. The disadvantage is that HDA still requires a relatively big amount of DNA, so it presumably will not be used in cases where high precision is needed.

References

doi:10.1038/sj.embor.7400200 Published online: 9 July 2004

01-04-2007 01:16:19
The contents of this article are licensed from Wikipedia.org under the GNU Free Documentation License. How to see transparent copy