What is PCR Diagnostics?

Detection of pathogens is accompanied by the delivery of tests. We hardly read incomprehensible words on the direction. Often there is a method of laboratory diagnosis, such as polymerase chain reaction. What is PCR? Let's understand.

History

The method was created by Cary Myullis in 1983. For him, the scientist was awarded the Nobel Prize. Initially, the method was planned for use for scientific purposes, but, seeing its effectiveness and prospects, began to advance innovation in practical medicine.

Sometimes to the question: "What is PCR?" They answer that this is the technique of finding a needle in a haystack. By the needle here is meant a fragment of the genetic material of the microorganism, and hay is the human body.

Principle of operation

In the body, DNA is responsible for genetic information. Nucleotides of adjacent spirals are connected in the established order. Every living organism has its own DNA - it does not matter whether it's an animal, an animal, a virus or a bacterium. To identify the body needs a small area of genetic storage. It happens that microorganisms (the immunodeficiency virus) store information in ribonucleic acid, but this method finds its fragments.

You still do not understand what is PCR and how does it work? Know, its principle is built on the discovery of a unique site. After all, for all pathogens there are specific genetic detectors, reference DNA fragments. They catch "their piece" and start the reaction of making copies.

In three minutes (one cycle), the number of copies grows at times. And in a few hours the number of fragments increases by billions of times. Therefore, it is easy to identify the causative agent of infection.

Answering the question, what is PCR, one can not ignore the pros and cons of this method.

Pluses:

• Versatility. When other methods are powerless, the PCR analysis is potent. It detects any RNA and DNA on standard equipment.

• High specificity. The nucleotide sequence is characteristic of only one particular pathogen. That is, the guarantee is 100%. Also, the material under study can be directed to the detection of several microorganisms simultaneously. This does not affect the quality of the answer.

• Sensitivity. You can find the smallest fragment of the microorganism.

• Efficiency. PCR is a diagnosis in a few hours. From the delivery of material until the result is obtained no more than one day.

• Determination of the pathogen in the incubation period. Even if there are no visible signs of the disease, the method will be able to diagnose the pathogen and determine the disease.

disadvantages

"PCR - what is it?" The uninformed ask. But we already know that this is an effective method of searching for an infectious agent. Unfortunately, he has drawbacks. For example, there is a "false alarm", as in the air there is a cocktail of DNA fragments of many living organisms - and during the reaction the sample can "get dirty". To prevent this, a biological filter is installed in the room.

Evaluate the results of tests should a specialist. Since a positive response does not always mean the presence of a disease. Some residual pathogens after treatment live in the body for several more months, without causing harm. A low titer shows that in life a person once encountered this microorganism.

Negative analysis in the presence of a clear picture of the disease indicates that the material was taken incorrectly (not from there or not according to instructions).

If you doubt the results of the analysis, retake them by another method or in another laboratory. The combination of several methods gives a 100% assessment of the body for the presence or absence of infectious agents. And remember: all the results of laboratory research should be shown to the doctor. Do not make independent conclusions and do not put yourself diagnoses!