“ It is a test tube method for amplifying a selected
DNA sequence that does not rely on the
biological cloning method.”
STEPS OF A POLYMERASE
Denature the DNA
Annealing of primers to single-stranded
ADVANTAGES OF PCR
Advantage over cloning – sensitivity and speed
DNA sequence present in an individual cell ;
scarce amounts can be studied.
DNA is very fast and technically less difficult
than traditional cloning methods using
recombinant DNA techniques.
PCR has become a very common tool for a large
number of applications
1)Comparison of a normal gene with a mutant form of
2)Detection of low-abundance nucleic acid sequences.
3)Forensic analysis of DNA samples.
4)Prenatal diagnosis and carrier detection of cystic
“ The simultaneous amplification of multiple
regions of a target DNA using multiple primer
pairs is known as multiplex PCR. It allows
detection of the loss of 1 or more exons in a
gene with many exons.”
Example : gene for CFTR which has 27 genes