APPLICATION OF POLYMERASE CHAIN REACTION(PCR)

 

APPLICATION OF POLYMERASE CHAIN REACTION(PCR)

                                                                                                                   

Let start from the definition of PCR,

INTRODUCTION

It is a method used to create million or billions of copy of DNA from the single sample by the means of continuous cloning.

           DNA sample → Multiple copy of DNA fragments

            

NOW,

General Application of PCR:

Ø In Bioremediation 

Ø  Genetic Engineering

Ø  In research       

Ø  In Genomic studies/Genotyping

Ø Evolutionary studies     

Ø In forensics science

Ø  Classification of organisms              

Ø  Genetic and Infectious diseases diagnosis

Ø  Detection of infection of environment

Ø It is time to explain about the application of PCR.

         1. Bioremediation (Bio + remediation)

It is a triple-corners process between pollutants, environment, organisms, where microorganisms are used for waste management. For this purpose, non-pathogenic microorganisms are required with degrading activities and by the support of these microbes’ conversion of hazardous substances into less toxic/non-toxic takes place. For this following condition/factor are required,

               Temperature= 0-40 degree Celsius

                pH= 6.5-7.5

          Types,

1.In-situ = If the biodegradation of the wastage takes place in the same environment where they are found.

2.Ex-situ = If the biodegradation of the wastage take place in the safer place away from the original place.

2.Genetic Engineering:

Preparation of multiple copy of DNA from the single copy of DNA is possible by the use of the PCR, which are required for the identification and analysis, Similarly, gene manipulation is also possible via the use of PCR, which include hybridization, addition or deletion of certain segments of gene. Such gene manipulation is useful in the process of production of transgenic animal.

        3.Genetic and Infectious disease diagnosis

 Identification of genetic diseases even before the birth of baby is possible via the use of PCR, which help to prevent the possible risk of transferring genetic diseases to the newcomers. It is possible by the following screening,

a. Genetic counselling: Screening the patients for genetic disease.

It includes the screening the genetic condition of patients, whether they have or don’t have any sort of genetic defects. If they have any genetic defects, they are suggested not to conceive any baby.

b. Preimplantation diagnosis: Screening of genetic disease before embryo implantation in IVF.

Screening of semen from father and ovum from the mother are done before the fertilization and implantation, which prevent the risk of transferring the genetic defects to the offspring’s.

c. Screening of genetic disease by using tissue samples from chorionic villus, amniotic fluid, foetal DNA.

Similarly, diagnosis of any congenital defects in the fetus is done by screening the chorionic villus, amniotic fluid and fetal DNA too.

It is also possible to diagnose the infectious disease by the use of PCR before the serological diagnosis.

        4.Detection of infection in Environment:

Detection of presence of any foreign materials in the environmental components is also possible by the amplification of sample of environmental components.

        5.Forensic Science:

Criminal investigation:

Sample collected from the crime sites are amplified by using the PCR and detection of the criminal by observing the similarities between the DNA sample of the suspected person and the sample from sites.

Less discriminating form of fingerprinting is used for DNA paternity testing:

If anyone accused someone as his/her biological parents then under the order of the court they are allowed to check it by extracting certain volume of blood from both parents and the and baby, then extracts the DNA from the blood and multiply it via PCR and observe the similarity.

Even for real time sex determination from forensics bone sample:

By observing the following characters, we are able to separate the male and female from the given sample of bone,

            6.Research:

PCR assisted DNA Sequencing:

It is possible to identify the original sequence of the unknown DNA sample by the process called as DNA Sequencing which requires the PCR to amplify the small fragment of DNA/Probe.

Study of the pattern of gene expression:

It is also used to observe the actual pattern of gene expression.

Phylogenic analysis of DNA from ancient's sources:

PCR is also used to determine the gradual process of development of the individual in different period of time by observing the DNA obtained during the paleontological studies.

Sequence-tagged sites:

DNA cloning:

Preparation of multiple copies of DNA is possible via the use of the PCR, which is further possible to use for any purpose according to our wishes.

          7. Evolutionary Studies:

DNA obtained during the paleontological studies are multiplied by the DNA, which are useful during the process of determining the gradual process of development of individual from past to present.