DNA testing. How are DNA tests done

O DNA (deoxyribonucleic acid) is one of the nucleic acids and can be found both inside and outside of cells. although the DNA has become known only in recent decades due to the popularization of tests for identifying dubious paternity, he was already known in the scientific community since the beginning of the 1950s, when he became proven that the DNA it's the stuff that makes up the genes. ThroughDNA it is possible to identify people to clarify a possible participation in a crime and also in carrying out paternity tests. It is important to remember that, with the exception of identical twins, each person's DNA is unique.

O test ofDNA, called DNA figerprint or genetic fingerprint, provides a very high degree of reliability, surpassing 99.9% certainty in its result. Because of this, this test is often used in determining paternity and solving crimes.

In order for a person to be identified through their DNA probes capable of detecting sequences from the DNA human. These sequences of DNA are called

VNTR (Variable Number of Tandem Repeats - variable number of repeats in sequence) and are composed of short nucleotide sequences that are repeated along stretches of the molecule. DNA. Each person has a specific pattern of repeating these units and that pattern is inherited from their parents.

Do not stop now... There's more after the advertising ;)

When samples of DNA are obtained through hair, blood, pieces of skin, sperm, etc., isolation of the DNA using restriction enzymes. After using the enzymes, the DNA it becomes fragmented, that is, separated into small pieces. These small pieces are then separated in a process called electrophoresis, which uses electrical current. After the end of the electrophoresis, equipment that uses ultraviolet light and a specific dye translates the DNA image, which can then be studied by the researchers.

The tracks observed are unique for each person and that is why it is called DNA fingerprint or genetic fingerprint.


By Paula Louredo
Graduated in Biology

Would you like to reference this text in a school or academic work? Look:

MORAES, Paula Louredo. "DNA test"; Brazil School. Available in: https://brasilescola.uol.com.br/biologia/teste-de-dna.htm. Accessed on June 28, 2021.

Tasmanian Devil: Characteristics and Trivia

Tasmanian Devil: Characteristics and Trivia

The Tasmanian Devil (Sarcophilus harrisii) is a marsupial mammal, native to the island of Tasmani...

read more

Mutation: concept, types, examples in humans

A mutation can be defined as any change in the genetic material of an organism.This change can ca...

read more
ABO System and RH Factor

ABO System and RH Factor

O ABO system they are classifications of human blood into the four existing types: A, B, AB and O...

read more