Detecting excrement is a technical task, which is equivalent to going to the hospital for a physical examination, and the doctor will ask for a fecal test.

Gu Chen is not afraid of Officer Wang's jokes, anyway, at present, the important clues have not yet been found, and going to the technical department with bird droppings and bread crumbs by himself can be regarded as a kind of busyness.

By the way, it was also time to return the manuscript to the forensic assistant yourself.

It would be a bit unreasonable to say that although the observation power that has just been upgraded to the specialty level is very strong, he has not achieved anything in the residence of Aguta Takasugi.

Of course, after careful investigation, the information captured by the specialized observation power is also complete.

After investigating the whole room, no suspicious points were found, but Gu Chen was the only one who had a soft spot for the dead canary, as well as the bird droppings and bread crumbs left on the ground.

I always feel that there is a flaw in my observational ability?

Or in the process of promotion, there is a deviation in the observation of details, and the original inconsequential places are over-interpreted.

But the problem is that after the investigation of a series of cases, I have also verified the excellence of my various skills one by one, and it seems that there is no so-called deviation, and it is even more accurate than the observation of ordinary old comrades.

However, Gu Chen did not expect that he would be overconfident in future cases with his previous experience.

The vast majority of unjust, false and wrongly decided cases often lie in the police's excessive belief in the so-called experience of handling cases.

In some unconventional cases, it is often necessary to break the routine and investigate from another perspective, and perhaps find unexpected clues.

Gu Chen is not competing with guano now, if it wasn't for the inconvenience at that time, he would have taken it away with the canary corpse.

Although it sounds ridiculous......

Officer Wang drove the car to the compound of the city bureau, under the building where the technical section was located.

"Gu Chen, I persuaded myself to bring you over, that is absolute trust in you. "Officer Wang spoke strangely.

"So what?" asked Gu Chen.

"You can go up by yourself later, don't say that I brought you here, okay?" Officer Wang looked at Gu Chen with a bitter face.

Gu Chen nodded: "I know, then I'll go over first." ”

Opening the car door, Gu Chen was about to go alone, but at this time, Lu Weiwei stopped him: "Senior Brother Gu, I'll go with you." ”

"Okay. ”

The two left side by side, leaving only Officer Wang in the car at a loss.

"It's okay if one person goes to lose face, but what's the point if two people go? Aren't you afraid of being laughed at by comrades in the city bureau?"

Since he was about to be on the honor roll, Officer Wang suddenly felt that he was also a face-saving person.

It doesn't matter if the case is blocked, follow two subordinates to add blockage to people, such a thing...... I don't want a second time.

Gu Chen and Lu Weiwei took the elevator and went directly to the fifth floor of the building.

This is the location of the technical department, although there are not many personnel, but there are many laboratories, and various testing instruments are quite complete.

As soon as he entered the door, Gu Chen saw the forensic assistant who had lent him the manuscript before, and he immediately called Senior Brother Wu.

The forensic assistant narrowed his eyes, turned around and exclaimed, "Aren't you that Gu Chen?"

"Yes, Senior Brother Wu. ”

"What are you doing here?"

"Return your manuscript. Gu Chen handed him the manuscript in his hand.

The forensic assistant was stunned and looked at him incredulously: "Gu Chen, you're done reading it all, not so fast, right?"

In the impression of forensic assistants, it is also unrealistic to want to master the essence in a few months.

And Gu Chen usually has to go to work, thinking that he should take photos first, and then organize and study when he is free, it should be like this.

"It's really done. Gu Chen also said modestly: "Senior Brother Wu's record is very detailed, which has benefited me a lot. ”

The forensic assistant took the manuscript, examined it carefully, and said casually: "Okay, I'll be busy with nothing first, so I won't send it to you." ”

"Don't. Lu Weiwei suddenly stopped him: "We are looking for Forensic Doctor Liu, is he there?"

"Yes, in testing room two, you can go over by yourself. The forensic assistant looked very busy, and after a few brief explanations, he left first.

Gu Chen and Lu Weiwei found the No. 2 testing room by themselves......

At this moment, Forensic Doctor Liu is writing a report on his desk, and it seems that he has just completed a test.

Gu Chen knocked on the door and walked in: "Forensic Doctor Liu, I'm here to trouble you again." ”

Forensic Doctor Liu raised his head and pushed his glasses: "Yo! It's Gu Chen and Weiwei, why are you here?"

"There's a couple of things I'd like you to help you test it out. Gu Chen took out the document bag.

"In a hurry?" asked Forensic Doctor Liu with a glare.

"Yes, it's very urgent, and it's best to take it away after testing. "Gu Chen is also an anxious person, since he personally sent it to the technical department, he doesn't want to run again.

"But I still have a report in my hand. ”

"Forensic Doctor Liu, just help, cut in line. Lu Weiwei said with a pretentious face.

As we all know, forensic examines take time.

If you are busy, many test items need to be queued for testing, after all, everyone hopes that the results will be available in the shortest possible time.

Forensic Doctor Liu nodded, and said with a smile: "Okay, for the sake of the two of you personally sending it over, then bring it, it just so happens that I am not in a hurry with this report." ”

"That's great. Gu Chen hurriedly opened the file bag and handed several copies of bird droppings and bread crumbs to Forensic Doctor Liu at the same time.

"You want to test your stool?" asked Forensic Doctor Liu.

"This is the feces of a canary, and I suspect that this canary may have eaten poisonous substances, so ......"

Gu Chen also expressed his guess.

Forensic Doctor Liu partnered with Gu Chen many times, and quickly understood what he meant.

Although I don't know if there is any necessary connection between this and the case, it will definitely help Gu Chen in handling the case.

"Wait a minute. Forensic Doctor Liu didn't say a word, took the sample and went to the instrument.

Nowadays, forensic testing of excrement is not as cumbersome as before, but most of the excrement is extracted from people.

However, it is still difficult to extract human DNA, but it may be possible to identify the person's DNA.

The reason why it is difficult to extract is that feces contains undigested DNA fragments from food.

The DNA of the gut microbe, and the DNA from the cells shed from the owner's digestive tract, are essentially the same, and there is no way to separate the person's DNA from the others.

But for the most of the things that need to be identified, it is feasible to identify its owner from fecal DNA.

There are parts of human DNA that are highly variable regions that are different from each person and require only one specific gene amplification method.

This is also known as PCR, polymerase chain reaction.

Amplify this highly variable region, identify the sequence of this segment, and compare it with a database, or a person's DNA, to know the correspondence between the feces and the owner.

In other words, you don't need to extract all the DNA, you just need to identify the DNA.

In fact, forensic examinations are carried out in this way.

And the results that Gu Chen needs are actually much simpler than identifying DNA, just finding the correlation point from the animal's feces.

After comparing the data values, Liu forensic medicine told Gu Chen: "I can tell you now that these bread crumbs do contain highly toxic substances, and there are also in feces. ”

Gu Chen's eyes lit up, this was the result he wanted, it seemed that the clues that had been interrupted earlier suddenly became one again.

"In other words, this canary died after eating this poisonous bread for a long time?"

Forensic Doctor Liu nodded: "That's right, it's indeed caused by long-term consumption, I have a copy of the test results here, you can take it first." ”

Gu Chen took the report, got up and bowed, "Thank you, Forensic Doctor Liu, thanks to your help this time." ”

"Small meaning. Forensic Doctor Liu laughed.

However, Lu Weiwei on the side was confused, and she hurriedly asked, "Senior Brother Gu, do you have any new discoveries?"

Gu Chen said mysteriously: "Let's talk in detail later, didn't Senior Brother Wang want me to find clues to report? It just so happens that I have a basis now." ”