Polymerase Chain Reaction Report

1.Polymerase chain reaction (PCR):

Polymerase chain reaction is a method of DNA or RNA amplification . The PCR method allows millions of copies to be created from a very small DNA section. The PCR methodology was developed in 1983 by Kary Mull , who in 1993 received a Nobel Prize for Chemistry with Michael Smith

PRINCIPLE & PROCEDURES:

1.DNA denaturation. Once the DNA has been isolated and purified from the cell, a PCR assay can begin. Uncleaned DNA can also be used for PCR, but it is ineffective. To denature the DNA, the DNA is heated at 90-95 ° C, during which the DNA is bihelixdisintegrates into two single cells. This is necessary to reproduce the interesting fragments. Synthesis can occur only from a single chain.

2. Primer binding

DNA synthesis. When primers detect and limit the amplification DNA sequence on two sides, the thermostable DNA polymerase synthesizes a complementary fragment from the 3 'end of the primers from both DNA single chain fragments using the nucleotides added to the mixture. The procedure is carried out at 72 ° C, using a thermostable Taq polymerase.

APPLICATIONS: The ability of the PCR to analyze a very small amount of DNA plays an important role in disease diagnostics. One of the important uses of PCR is the diagnosis of possible AIDS infection at a very early stage even before antibodies have developed . This is especially important due to the long delay in viruses. Thanks to PCR, a DNA fragment of an HIV-infected isolated human leukocyte can be reproduced until a sufficient amount of material has been obtained for analysis.

PCR can also be used to preimplant- diagnose, for example, to detect cystic fibrosis . For the assay are isolated from the in vitro generated from the eight-cell embryo at the one cell. It is extracted from DNA and amplified with a primer-delimited fragment (the cystic fibrosis causing sequence in DNA is known). The fragments obtained are analyzed on electrophoresis. Only a disease-free embryo is used for

They are used due to their ability to infect a cell and integrate their genetic material into the host.

Two types of gene therapy are:

1. Somatic gene therapy2. Germline gene therapy

Gene therapy mainly targets single-gene recessive disorders, viral infections and acquired genetic diseases.

Ethical issues arise when considering gene therapy due to a vast majority of reasons. Deciding weather a disease is worthy of getting the treatment is one of the major issues.

4. Stem Cell Therapy

Stem cell therapy is widely used to treat and prevent diseases. Most common type is bona marrow transplant. It is a process in which stem cells are extracted from a healthy individual and targeted at the damaged tissue in order to repair it.

Stem cells are used because of their ability for self-renewal is magnificent where they can be used to target any type of tissue.

Risk of rejection is minimised when using stem cell therapy as ones own stem cells can be used.

Stem cell therapy can be complicated due to its procedure. First of all, the defected bone marrow must be destroyed which arises a huge risk to new diseases. Healthy stem cells are then introduced and the patient is given time to recover where blood counts are monitored