From the theater viewing experience Have
xo wallet you seen a DNA test to prove your characters' blood ties? Most of the drama's character DNA testing uses "hair", but do you want to know if "hair" can actually be used for DNA testing? Which we must first get to know each other DNA
What is DNA?
DNA has the full name Deoxyribonucleic acid Deoxyribonucleic acid is a type of nucleic acid that contains the genetic material that is a component of living organisms. Which is responsible for storing genetic information And inheritance of the genetic code (the part of the DNA that contains the genetic information, the gene: gene), which plays an important role in determining the characteristics of living organisms.
DNA thus allows living organisms to inherit characteristics of ancestors. And sustain the species from generation to generation. DNA will look like a twisted pair of spiral staircase in the chromosome (chromosome) and mitochondria. (mitochondrion) of humans
We all have two DNA strands. The first is intracellular DNA organized into a long structure. Called chromosomes Humans inherit this DNA from half the father and half of the mother. The second is located in the mitochondria. This part will be transmitted from all mothers. (In this section, the lineage can be traced with a relative on the mother's side)
Within DNA there is a component called a nucleotide.The nucleotide sequencing is different, making the DNA look like our fingerprints. Is unique Chances are that the nucleotide arrangements are the same. It is almost impossible. Therefore, the DNA code test is very accurate. Because of the likelihood that our human beings will look the same Completely matched, every position is almost nonexistent.
When all human beings have a person's DNA, so DNA can be used to prove a person's identity. And prove the relationship of blood, such as the found anonymous body that can not determine who the deceased is. Forensic medicine will bring the parents who lost their children. I suspect that this is my own child's corpse to collect DNA to compare it with DNA obtained from the corpse. If the DNA matches, the body can be identified.
The part we often see in dramas is the DNA test to look for blood ties. If it's a hand-in-hand verification, there are no problems. But the problem is "Keeping the hair" that fell on the floor Or hair stuck at the comb Go to check separately Which in fact Can we get DNA from the hair?
Can we get DNA from the hair?
The answer is that we can actually test the DNA from the hair. But… the hair that is examined must only have “cells”, which are components of the human body. It is very unlikely that the hair is falling off the floor. Or the hair attached to the comb will have a part of the cell, that is, "hair root: hair root" (a white blister attached to the hair. If we pull out the hair with care) is stuck, including the hair cut by scissors. (No root of hair for sure) can not be used for DNA testing.
In addition to testing DNA from hair roots, other conditions are involved, such as the environment. If the hair that has been attached to the roots Is kept at a temperature below freezing (Negative cold temperature) dry, not exposed to air. Not exposed to moisture Not exposed to heat or sunlight, the DNA at the hair roots will keep very long. May last for many years
But in normal temperature environment Hair roots are exposed to air There are heat, humidity, sunlight, DNA will have a shorter lifespan. But the long retention period without being kept in the right environment could not test the DNA from the hair.
Why can't normal hair detect DNA?
So do you wonder why hair (Which is one of the components in the body) can not be used to detect DNA.
That's because the hair grows. And grow out of the scalp Until covering the head Are the dead cells Hair cells are not alive. No feeling The part that we still have long. Because the hair cells will gradually Grows from the roots of the hair from the roots of the hair (The part that is attached to the scalp) does not grow from the end of the hair, as many people still misunderstand.
If you still can't see the picture To think of people who have colored their hair The longer part is the root of the hair. (Because the length of the roots of the hair is natural hair color), the part of the hair that is colored will gradually move down to the end of the hair. If we cut it off Color will be gone there.
Therefore, it can be concluded that "hair" can be used for DNA testing with the condition that there must be a sufficient number of hair roots to be maintained in a suitable environment. And should not be contaminated by exposure
Hence, hair is not the best source of DNA. To be precise, we examine the DNA from the buccal mucosa or blood or human secretions. The DNA from the corpse can use fragments. Skeletal tissue fragments, bone fragments from a corpse
