PCR technique

Pcr, pcr technique, DNA,chain reaction, medical, college, enzymes.

A PCR technique! are you heard about this? of course! you must heard about this from your class teacher or science magnize or something like net source. Here you will know much more about this term. Lets know about this.

PCR

PCR stands for polimearse chain reactions. A technique mainly used to amplify, or we can say make many copies of a specific target region of DNA.

Key points :

• Polymearse chain reaction, or PCR  is technique used i to make many copies of a specific DNA region in a laborartry.

• In PCR a Taq polymearse, and DNA primer is designed specifically for interest DNA region.

• In PCR technique, The reaction is repeatediy cycled through a series of tempertature changes, Which allowmanycopies of the target region to be produced.

• PCR technique is widely used in scientifics reaseaech, forencisic science, DNA cloning, Medical diagonatics and scientifics analysis of DNA.

WHAT IS PCR

Pcr is a technique widely used in laboartory. we used this technique for many copies of dna (million or billion) of a specific dna segment.This DNA region can be anything the experimeter is in intersted in.
Typically, we can say the goal of pcr is to make enough of the target DNA region that it can be  lymearse is a synthetic enzyme that produces DNA strands at faster rate than natural polymerase. it is enzyme that copies DNA. it is isolated from a heat-loving bacterium that is naturaly found in hot springs, so the enzyme doesnot break down at high tempertures necessary for copying DNA using polymearse chain reaction.

PCR PRIMERS

pcr technique requires pcr primers, to begin DNA strand replication. An incorrect pcr primers can lead to failed reaction one in which the wrong gene fragement or no fragement issynthesis. An important factors for primers design are melting temperature, annealing, promoters region, and unique sequence target.universal and random primers are appropriate for general insert and multiple site copying,and are available with flourescein or radiolableing for quantative detection.

STEPS OF PCR

THE BASIC STEPS :

1. DENATURERATION (96℃) : In this technique heat reaction strongly separated or we can say denatur, the DNA strand. This technique provide single standed template for the next step.
2. Annwaling (55 - 65℃) : For this process, cool the reaction so the primers can bind to there complementary sequences on the single-stranded template DNA.
3. EXTENSION (72℃) : Raise the reaction temperature so TAQ polymerase extends the primer, synthesizing new strands of DNA.

This cycle repeats 25 - 35 times in a typical PCR reaction, which generally takes 2 - 4 hours, depending on the length of DNA region being copied. If the reaction is efficient or works well. the target reagion can go form just one or a few copies to billions.

APPLICATION OF PCR

1. PCR IN DNA SEQUENCING : As the PCR technique is much simpler and quicker to amplify the DNA sequence. For this propose, single strand are required. In aonther mehthod, Strand removal can be achieved by digesting one strand.
2. DIAGONIS OF CANCER: Several virally-induced cancers can be deteched by pcr. Further,some cancers which occur due to chromosomal translocation involving known genes are identified by pcr.
3. PCR IN SEX DETERMINATION OF EMBRYOS: Sex of human or liverstock embyos fertilised in vitro, can be determined by pcr, by using primers and DNA probes specific for sex chromoes. Further, this technique is also useful to detect sex linked disorders in fertilised embroys. 
4. PCR IN FORENSIC MEDICINE: Asingle molecule of DNA from any source(hair, semem,blood strains etc.)of an individul is adequate for amplification by PCR. PCR is very important for identification of criminials.
5. PCR IN GENE MANIPULATION AND EXPRESSION STUDIES: The advantage of pcr is that the primers need not have complememtary sequences for the target DNA. Therefore, the sequence of nucleotides in a piece of the gene can be manipulated and amplified by PCR.